Atrophy of the optic disk which may be congenital or acquired. This condition indicates a deficiency in the number of nerve fibers which arise in the RETINA and converge to form the OPTIC DISK; OPTIC NERVE; OPTIC CHIASM; and optic tracts. GLAUCOMA; ISCHEMIA; inflammation, a chronic elevation of intracranial pressure, toxins, optic nerve compression, and inherited conditions (see OPTIC ATROPHIES, HEREDITARY) are relatively common causes of this condition.
Dominant optic atrophy is a hereditary optic neuropathy causing decreased visual acuity, color vision deficits, a centrocecal scotoma, and optic nerve pallor (Hum. Genet. 1998; 102: 79-86). Mutations leading to this condition have been mapped to the OPA1 gene at chromosome 3q28-q29. OPA1 codes for a dynamin-related GTPase that localizes to mitochondria.
Hereditary conditions that feature progressive visual loss in association with optic atrophy. Relatively common forms include autosomal dominant optic atrophy (OPTIC ATROPHY, AUTOSOMAL DOMINANT) and Leber hereditary optic atrophy (OPTIC ATROPHY, HEREDITARY, LEBER).
A maternally linked genetic disorder that presents in mid-life as acute or subacute central vision loss leading to central scotoma and blindness. The disease has been associated with missense mutations in the mtDNA, in genes for Complex I, III, and IV polypeptides, that can act autonomously or in association with each other to cause the disease. (from Online Mendelian Inheritance in Man, http://www.ncbi.nlm.nih.gov/Omim/, MIM#535000 (April 17, 2001))
A rare degenerative inherited eye disease that appears at birth or in the first few months of life that results in a loss of vision. Not to be confused with LEBER HEREDITARY OPTIC NEUROPATHY, the disease is thought to be caused by abnormal development of PHOTORECEPTOR CELLS in the RETINA, or by the extremely premature degeneration of retinal cells.
Decrease in the size of a cell, tissue, organ, or multiple organs, associated with a variety of pathological conditions such as abnormal cellular changes, ischemia, malnutrition, or hormonal changes.
The 2nd cranial nerve which conveys visual information from the RETINA to the brain. The nerve carries the axons of the RETINAL GANGLION CELLS which sort at the OPTIC CHIASM and continue via the OPTIC TRACTS to the brain. The largest projection is to the lateral geniculate nuclei; other targets include the SUPERIOR COLLICULI and the SUPRACHIASMATIC NUCLEI. Though known as the second cranial nerve, it is considered part of the CENTRAL NERVOUS SYSTEM.
A hereditary condition characterized by multiple symptoms including those of DIABETES INSIPIDUS; DIABETES MELLITUS; OPTIC ATROPHY; and DEAFNESS. This syndrome is also known as DIDMOAD (first letter of each word) and is usually associated with VASOPRESSIN deficiency. It is caused by mutations in gene WFS1 encoding wolframin, a 100-kDa transmembrane protein.
The portion of the optic nerve seen in the fundus with the ophthalmoscope. It is formed by the meeting of all the retinal ganglion cell axons as they enter the optic nerve.
Enzymes that hydrolyze GTP to GDP. EC 3.6.1.-.
The inability to see or the loss or absence of perception of visual stimuli. This condition may be the result of EYE DISEASES; OPTIC NERVE DISEASES; OPTIC CHIASM diseases; or BRAIN DISEASES affecting the VISUAL PATHWAYS or OCCIPITAL LOBE.
Derangement in size and number of muscle fibers occurring with aging, reduction in blood supply, or following immobilization, prolonged weightlessness, malnutrition, and particularly in denervation.
Inflammation of the optic nerve. Commonly associated conditions include autoimmune disorders such as MULTIPLE SCLEROSIS, infections, and granulomatous diseases. Clinical features include retro-orbital pain that is aggravated by eye movement, loss of color vision, and contrast sensitivity that may progress to severe visual loss, an afferent pupillary defect (Marcus-Gunn pupil), and in some instances optic disc hyperemia and swelling. Inflammation may occur in the portion of the nerve within the globe (neuropapillitis or anterior optic neuritis) or the portion behind the globe (retrobulbar neuritis or posterior optic neuritis).
Enzymes that catalyze the rearrangement of geometry about double bonds. EC 5.2.
The record of descent or ancestry, particularly of a particular condition or trait, indicating individual family members, their relationships, and their status with respect to the trait or condition.
A group of slowly progressive inherited disorders affecting motor and sensory peripheral nerves. Subtypes include HMSNs I-VII. HMSN I and II both refer to CHARCOT-MARIE-TOOTH DISEASE. HMSN III refers to hypertrophic neuropathy of infancy. HMSN IV refers to REFSUM DISEASE. HMSN V refers to a condition marked by a hereditary motor and sensory neuropathy associated with spastic paraplegia (see SPASTIC PARAPLEGIA, HEREDITARY). HMSN VI refers to HMSN associated with an inherited optic atrophy (OPTIC ATROPHIES, HEREDITARY), and HMSN VII refers to HMSN associated with retinitis pigmentosa. (From Adams et al., Principles of Neurology, 6th ed, p1343)
The X-shaped structure formed by the meeting of the two optic nerves. At the optic chiasm the fibers from the medial part of each retina cross to project to the other side of the brain while the lateral retinal fibers continue on the same side. As a result each half of the brain receives information about the contralateral visual field from both eyes.
Double-stranded DNA of MITOCHONDRIA. In eukaryotes, the mitochondrial GENOME is circular and codes for ribosomal RNAs, transfer RNAs, and about 10 proteins.
Neurons of the innermost layer of the retina, the internal plexiform layer. They are of variable sizes and shapes, and their axons project via the OPTIC NERVE to the brain. A small subset of these cells act as photoreceptors with projections to the SUPRACHIASMATIC NUCLEUS, the center for regulating CIRCADIAN RHYTHM.
Swelling of the OPTIC DISK, usually in association with increased intracranial pressure, characterized by hyperemia, blurring of the disk margins, microhemorrhages, blind spot enlargement, and engorgement of retinal veins. Chronic papilledema may cause OPTIC ATROPHY and visual loss. (Miller et al., Clinical Neuro-Ophthalmology, 4th ed, p175)
Visual impairments limiting one or more of the basic functions of the eye: visual acuity, dark adaptation, color vision, or peripheral vision. These may result from EYE DISEASES; OPTIC NERVE DISEASES; VISUAL PATHWAY diseases; OCCIPITAL LOBE diseases; OCULAR MOTILITY DISORDERS; and other conditions (From Newell, Ophthalmology: Principles and Concepts, 7th ed, p132).
Recording of electric potentials in the retina after stimulation by light.
Clarity or sharpness of OCULAR VISION or the ability of the eye to see fine details. Visual acuity depends on the functions of RETINA, neuronal transmission, and the interpretative ability of the brain. Normal visual acuity is expressed as 20/20 indicating that one can see at 20 feet what should normally be seen at that distance. Visual acuity can also be influenced by brightness, color, and contrast.
Injuries to the optic nerve induced by a trauma to the face or head. These may occur with closed or penetrating injuries. Relatively minor compression of the superior aspect of orbit may also result in trauma to the optic nerve. Clinical manifestations may include visual loss, PAPILLEDEMA, and an afferent pupillary defect.
The ten-layered nervous tissue membrane of the eye. It is continuous with the OPTIC NERVE and receives images of external objects and transmits visual impulses to the brain. Its outer surface is in contact with the CHOROID and the inner surface with the VITREOUS BODY. The outer-most layer is pigmented, whereas the inner nine layers are transparent.
A group of disorders marked by progressive degeneration of motor neurons in the spinal cord resulting in weakness and muscular atrophy, usually without evidence of injury to the corticospinal tracts. Diseases in this category include Werdnig-Hoffmann disease and later onset SPINAL MUSCULAR ATROPHIES OF CHILDHOOD, most of which are hereditary. (Adams et al., Principles of Neurology, 6th ed, p1089)
Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.
Biochemical identification of mutational changes in a nucleotide sequence.
'Eye proteins' are structural or functional proteins, such as crystallins, opsins, and collagens, located in various parts of the eye, including the cornea, lens, retina, and aqueous humor, that contribute to maintaining transparency, refractive power, phototransduction, and overall integrity of the visual system.
Genes that influence the PHENOTYPE only in the homozygous state.
Filarial infection of the eyes transmitted from person to person by bites of Onchocerca volvulus-infected black flies. The microfilariae of Onchocerca are thus deposited beneath the skin. They migrate through various tissues including the eye. Those persons infected have impaired vision and up to 20% are blind. The incidence of eye lesions has been reported to be as high as 30% in Central America and parts of Africa.
Diseases affecting the eye.
Diseases caused by abnormal function of the MITOCHONDRIA. They may be caused by mutations, acquired or inherited, in mitochondrial DNA or in nuclear genes that code for mitochondrial components. They may also be the result of acquired mitochondria dysfunction due to adverse effects of drugs, infections, or other environmental causes.
A flavoprotein and iron sulfur-containing oxidoreductase that catalyzes the oxidation of NADH to NAD. In eukaryotes the enzyme can be found as a component of mitochondrial electron transport complex I. Under experimental conditions the enzyme can use CYTOCHROME C GROUP as the reducing cofactor. The enzyme was formerly listed as EC 1.6.2.1.
In invertebrate zoology, a lateral lobe of the FOREBRAIN in certain ARTHROPODS. In vertebrate zoology, either of the corpora bigemina of non-mammalian VERTEBRATES. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed, p1329)
A retrogressive pathological change in the retina, focal or generalized, caused by genetic defects, inflammation, trauma, vascular disease, or aging. Degeneration affecting predominantly the macula lutea of the retina is MACULAR DEGENERATION. (Newell, Ophthalmology: Principles and Concepts, 7th ed, p304)
Ischemic injury to the OPTIC NERVE which usually affects the OPTIC DISK (optic neuropathy, anterior ischemic) and less frequently the retrobulbar portion of the nerve (optic neuropathy, posterior ischemic). The injury results from occlusion of arterial blood supply which may result from TEMPORAL ARTERITIS; ATHEROSCLEROSIS; COLLAGEN DISEASES; EMBOLISM; DIABETES MELLITUS; and other conditions. The disease primarily occurs in the sixth decade or later and presents with the sudden onset of painless and usually severe monocular visual loss. Anterior ischemic optic neuropathy also features optic disk edema with microhemorrhages. The optic disk appears normal in posterior ischemic optic neuropathy. (Glaser, Neuro-Ophthalmology, 2nd ed, p135)
A syndrome complex composed of three conditions which represent clinical variants of the same disease process: STRIATONIGRAL DEGENERATION; SHY-DRAGER SYNDROME; and the sporadic form of OLIVOPONTOCEREBELLAR ATROPHIES. Clinical features include autonomic, cerebellar, and basal ganglia dysfunction. Pathologic examination reveals atrophy of the basal ganglia, cerebellum, pons, and medulla, with prominent loss of autonomic neurons in the brain stem and spinal cord. (From Adams et al., Principles of Neurology, 6th ed, p1076; Baillieres Clin Neurol 1997 Apr;6(1):187-204; Med Clin North Am 1999 Mar;83(2):381-92)
Glutarates are organic compounds, specifically carboxylic acids, that contain a five-carbon chain with two terminal carboxyl groups and a central methyl group, playing a role in various metabolic processes, including the breakdown of certain amino acids. They can also refer to their salts or esters. Please note that this definition is concise and may not cover all aspects of glutarates in depth.
The continuous visual field seen by a subject through space and time.
The total area or space visible in a person's peripheral vision with the eye looking straightforward.
The concave interior of the eye, consisting of the retina, the choroid, the sclera, the optic disk, and blood vessels, seen by means of the ophthalmoscope. (Cline et al., Dictionary of Visual Science, 4th ed)
The magnitude of INBREEDING in humans.
A mutation in which a codon is mutated to one directing the incorporation of a different amino acid. This substitution may result in an inactive or unstable product. (From A Dictionary of Genetics, King & Stansfield, 5th ed)
A disease that is characterized by frequent urination, excretion of large amounts of dilute URINE, and excessive THIRST. Etiologies of diabetes insipidus include deficiency of antidiuretic hormone (also known as ADH or VASOPRESSIN) secreted by the NEUROHYPOPHYSIS, impaired KIDNEY response to ADH, and impaired hypothalamic regulation of thirst.
An amino acid-specifying codon that has been converted to a stop codon (CODON, TERMINATOR) by mutation. Its occurance is abnormal causing premature termination of protein translation and results in production of truncated and non-functional proteins. A nonsense mutation is one that converts an amino acid-specific codon to a stop codon.
The continuous remodeling of MITOCHONDRIA shape by fission and fusion in response to physiological conditions.
A condition marked by progressive CEREBELLAR ATAXIA combined with MYOCLONUS usually presenting in the third decade of life or later. Additional clinical features may include generalized and focal SEIZURES, spasticity, and DYSKINESIAS. Autosomal recessive and autosomal dominant patterns of inheritance have been reported. Pathologically, the dentate nucleus and brachium conjunctivum of the CEREBELLUM are atrophic, with variable involvement of the spinal cord, cerebellar cortex, and basal ganglia. (From Joynt, Clinical Neurology, 1991, Ch37, pp60-1)
Vision considered to be inferior to normal vision as represented by accepted standards of acuity, field of vision, or motility. Low vision generally refers to visual disorders that are caused by diseases that cannot be corrected by refraction (e.g., MACULAR DEGENERATION; RETINITIS PIGMENTOSA; DIABETIC RETINOPATHY, etc.).
Proteins encoded by the mitochondrial genome or proteins encoded by the nuclear genome that are imported to and resident in the MITOCHONDRIA.
A characteristic symptom complex.
A group of recessively inherited diseases that feature progressive muscular atrophy and hypotonia. They are classified as type I (Werdnig-Hoffman disease), type II (intermediate form), and type III (Kugelberg-Welander disease). Type I is fatal in infancy, type II has a late infantile onset and is associated with survival into the second or third decade. Type III has its onset in childhood, and is slowly progressive. (J Med Genet 1996 Apr:33(4):281-3)
Semiautonomous, self-reproducing organelles that occur in the cytoplasm of all cells of most, but not all, eukaryotes. Each mitochondrion is surrounded by a double limiting membrane. The inner membrane is highly invaginated, and its projections are called cristae. Mitochondria are the sites of the reactions of oxidative phosphorylation, which result in the formation of ATP. They contain distinctive RIBOSOMES, transfer RNAs (RNA, TRANSFER); AMINO ACYL T RNA SYNTHETASES; and elongation and termination factors. Mitochondria depend upon genes within the nucleus of the cells in which they reside for many essential messenger RNAs (RNA, MESSENGER). Mitochondria are believed to have arisen from aerobic bacteria that established a symbiotic relationship with primitive protoeukaryotes. (King & Stansfield, A Dictionary of Genetics, 4th ed)
A specialized field of physics and engineering involved in studying the behavior and properties of light and the technology of analyzing, generating, transmitting, and manipulating ELECTROMAGNETIC RADIATION in the visible, infrared, and ultraviolet range.
A congenital abnormality in which the CEREBRUM is underdeveloped, the fontanels close prematurely, and, as a result, the head is small. (Desk Reference for Neuroscience, 2nd ed.)
The bridge between the inner and the outer segments of a retinal rod or a cone photoreceptor cell. Through it, proteins synthesized in the inner segment are transported to the outer segment.
Retinal diseases refer to a diverse group of vision-threatening disorders that affect the retina's structure and function, including age-related macular degeneration, diabetic retinopathy, retinal detachment, retinitis pigmentosa, and macular edema, among others.
Slender processes of NEURONS, including the AXONS and their glial envelopes (MYELIN SHEATH). Nerve fibers conduct nerve impulses to and from the CENTRAL NERVOUS SYSTEM.
Incoordination of voluntary movements that occur as a manifestation of CEREBELLAR DISEASES. Characteristic features include a tendency for limb movements to overshoot or undershoot a target (dysmetria), a tremor that occurs during attempted movements (intention TREMOR), impaired force and rhythm of diadochokinesis (rapidly alternating movements), and GAIT ATAXIA. (From Adams et al., Principles of Neurology, 6th ed, p90)
Defects of color vision are mainly hereditary traits but can be secondary to acquired or developmental abnormalities in the CONES (RETINA). Severity of hereditary defects of color vision depends on the degree of mutation of the ROD OPSINS genes (on X CHROMOSOME and CHROMOSOME 3) that code the photopigments for red, green and blue.
Glial cell derived tumors arising from the optic nerve, usually presenting in childhood.
The electric response evoked in the cerebral cortex by visual stimulation or stimulation of the visual pathways.
Hereditary, progressive degeneration of the neuroepithelium of the retina characterized by night blindness and progressive contraction of the visual field.
Non-invasive method of demonstrating internal anatomy based on the principle that atomic nuclei in a strong magnetic field absorb pulses of radiofrequency energy and emit them as radiowaves which can be reconstructed into computerized images. The concept includes proton spin tomographic techniques.
A group of disorders involving predominantly the posterior portion of the ocular fundus, due to degeneration in the sensory layer of the RETINA; RETINAL PIGMENT EPITHELIUM; BRUCH MEMBRANE; CHOROID; or a combination of these tissues.
An imaging method using LASERS that is used for mapping subsurface structure. When a reflective site in the sample is at the same optical path length (coherence) as the reference mirror, the detector observes interference fringes.
The outward appearance of the individual. It is the product of interactions between genes, and between the GENOTYPE and the environment.
Conditions which produce injury or dysfunction of the second cranial or optic nerve, which is generally considered a component of the central nervous system. Damage to optic nerve fibers may occur at or near their origin in the retina, at the optic disk, or in the nerve, optic chiasm, optic tract, or lateral geniculate nuclei. Clinical manifestations may include decreased visual acuity and contrast sensitivity, impaired color vision, and an afferent pupillary defect.
The co-inheritance of two or more non-allelic GENES due to their being located more or less closely on the same CHROMOSOME.
Naturally occurring or experimentally induced animal diseases with pathological processes sufficiently similar to those of human diseases. They are used as study models for human diseases.
A group of inherited and sporadic disorders which share progressive ataxia in combination with atrophy of the CEREBELLUM; PONS; and inferior olivary nuclei. Additional clinical features may include MUSCLE RIGIDITY; NYSTAGMUS, PATHOLOGIC; RETINAL DEGENERATION; MUSCLE SPASTICITY; DEMENTIA; URINARY INCONTINENCE; and OPHTHALMOPLEGIA. The familial form has an earlier onset (second decade) and may feature spinal cord atrophy. The sporadic form tends to present in the fifth or sixth decade, and is considered a clinical subtype of MULTIPLE SYSTEM ATROPHY. (From Adams et al., Principles of Neurology, 6th ed, p1085)
The presence of apparently similar characters for which the genetic evidence indicates that different genes or different genetic mechanisms are involved in different pedigrees. In clinical settings genetic heterogeneity refers to the presence of a variety of genetic defects which cause the same disease, often due to mutations at different loci on the same gene, a finding common to many human diseases including ALZHEIMER DISEASE; CYSTIC FIBROSIS; LIPOPROTEIN LIPASE DEFICIENCY, FAMILIAL; and POLYCYSTIC KIDNEY DISEASES. (Rieger, et al., Glossary of Genetics: Classical and Molecular, 5th ed; Segen, Dictionary of Modern Medicine, 1992)
An individual in which both alleles at a given locus are identical.
Specialized PHOTOTRANSDUCTION neurons in the vertebrates, such as the RETINAL ROD CELLS and the RETINAL CONE CELLS. Non-visual photoreceptor neurons have been reported in the deep brain, the PINEAL GLAND and organs of the circadian system.
A group of metabolic disorders primarily of infancy characterized by the subacute onset of psychomotor retardation, hypotonia, ataxia, weakness, vision loss, eye movement abnormalities, seizures, dysphagia, and lactic acidosis. Pathological features include spongy degeneration of the neuropile of the basal ganglia, thalamus, brain stem, and spinal cord. Patterns of inheritance include X-linked recessive, autosomal recessive, and mitochondrial. Leigh disease has been associated with mutations in genes for the PYRUVATE DEHYDROGENASE COMPLEX; CYTOCHROME-C OXIDASE; ATP synthase subunit 6; and subunits of mitochondrial complex I. (From Menkes, Textbook of Child Neurology, 5th ed, p850).
Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.
Proteins which are found in membranes including cellular and intracellular membranes. They consist of two types, peripheral and integral proteins. They include most membrane-associated enzymes, antigenic proteins, transport proteins, and drug, hormone, and lectin receptors.
Method of measuring and mapping the scope of vision, from central to peripheral of each eye.
Progressive, autosomal recessive, diffuse atrophy of the choroid, pigment epithelium, and sensory retina that begins in childhood.
A general term for the complete loss of the ability to hear from both ears.
The percent frequency with which a dominant or homozygous recessive gene or gene combination manifests itself in the phenotype of the carriers. (From Glossary of Genetics, 5th ed)
Transmission of gene defects or chromosomal aberrations/abnormalities which are expressed in extreme variation in the structure or function of the eye. These may be evident at birth, but may be manifested later with progression of the disorder.
Genes that influence the PHENOTYPE both in the homozygous and the heterozygous state.
Hearing loss resulting from damage to the COCHLEA and the sensorineural elements which lie internally beyond the oval and round windows. These elements include the AUDITORY NERVE and its connections in the BRAINSTEM.
A specific pair of human chromosomes in group A (CHROMOSOMES, HUMAN, 1-3) of the human chromosome classification.
Function of the human eye that is used in dim illumination (scotopic intensities) or at nighttime. Scotopic vision is performed by RETINAL ROD PHOTORECEPTORS with high sensitivity to light and peak absorption wavelength at 507 nm near the blue end of the spectrum.
A phenomenon that is observed when a small subgroup of a larger POPULATION establishes itself as a separate and isolated entity. The subgroup's GENE POOL carries only a fraction of the genetic diversity of the parental population resulting in an increased frequency of certain diseases in the subgroup, especially those diseases known to be autosomal recessive.
The genetic constitution of individuals with respect to one member of a pair of allelic genes, or sets of genes that are closely linked and tend to be inherited together such as those of the MAJOR HISTOCOMPATIBILITY COMPLEX.
Hereditary and sporadic conditions which are characterized by progressive nervous system dysfunction. These disorders are often associated with atrophy of the affected central or peripheral nervous system structures.
Subnormal intellectual functioning which originates during the developmental period. This has multiple potential etiologies, including genetic defects and perinatal insults. Intelligence quotient (IQ) scores are commonly used to determine whether an individual has an intellectual disability. IQ scores between 70 and 79 are in the borderline range. Scores below 67 are in the disabled range. (from Joynt, Clinical Neurology, 1992, Ch55, p28)
A form of MACULAR DEGENERATION also known as dry macular degeneration marked by occurrence of a well-defined progressive lesion or atrophy in the central part of the RETINA called the MACULA LUTEA. It is distinguishable from WET MACULAR DEGENERATION in that the latter involves neovascular exudates.
'Abnormalities, Multiple' is a broad term referring to the presence of two or more structural or functional anomalies in an individual, which may be genetic or environmental in origin, and can affect various systems and organs of the body.
The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.
Detection of a MUTATION; GENOTYPE; KARYOTYPE; or specific ALLELES associated with genetic traits, heritable diseases, or predisposition to a disease, or that may lead to the disease in descendants. It includes prenatal genetic testing.

Leber's hereditary optic neuropathy (LHON/11778) with myoclonus: report of two cases. (1/183)

The previously unrecognised association of myoclonus in two patients with LHON with the 11778/ND4 pathogenic mutation is described. EEG failed to disclose epileptic figures, and a back averaging study suggested that myoclonus was cortical in origin in both patients.  (+info)

Organization of the human IMPG2 gene and its evaluation as a candidate gene in age-related macular degeneration and other retinal degenerative disorders. (2/183)

PURPOSE: To characterize the genomic organization of human IMPG2, the gene encoding the retinal interphotoreceptor matrix (IPM) proteoglycan IPM 200, to evaluate its relationship to IPM 150, and to evaluate its involvement in inherited retinopathies, such as age-related macular degeneration, retinitis pigmentosa, and Leber congenital amaurosis. METHODS: After isolation of human genomic clones, the structure of IMPG2 was determined by sequence analysis. Mutational analyses were conducted on genomic DNA isolated from 316 probands using single-strand conformation polymorphism analysis. RESULTS: The IMPG2 gene is organized into 19 exons, and the structure of the gene is highly similar to that of the IMPG1 gene, which encodes another retinal proteoglycan, IPM 150. Mutational analyses indicate that the observed sequence changes are present at approximately equal rates in donors with and without retinal disease. Additional data derived from RT-PCR and Northern blot analysis show that IMPG2 is processed in the human retina into multiple alternatively sized transcripts that may represent splicing isoforms. CONCLUSIONS: Analysis of the overall relationship of human IMPG2 (located on chromosome 3q12.2-12.3) to human IMPG1 (located on chromosome 6q14) suggests that these genes have evolved from a common ancestral gene. Although this is an excellent candidate gene for hereditary retinopathies, single-strand conformation polymorphism analyses provided no evidence that variations in IMPG2 coding region are responsible for the inherited retinopathies examined.  (+info)

Cells bearing mutations causing Leber's hereditary optic neuropathy are sensitized to Fas-Induced apoptosis. (3/183)

Three prevalent mitochondrial DNA pathogenic mutations at positions 11778, 3460, and 14484, which affect different subunits of Complex I, cause retinal ganglion cell death and optic nerve atrophy in Leber's hereditary optic neuropathy (LHON). The cell death is painless and without inflammation, consistent with an apoptotic mechanism. We have investigated the possibility that the LHON mutation confers a pro-apoptotic stimulus and have tested the sensitivity of osteosarcoma-derived cybrid cells carrying the most common and severe mutations (11778 and 3460) to cell death induced by Fas. We observed that LHON cybrids were sensitized to Fas-dependent death. Control cells that bear the same mitochondrial genetic background (the J haplogroup) without the pathogenic 11778 mutation are no more sensitive than other controls, indicating that increased Fas-dependent death in LHON cybrids was induced by the LHON pathogenic mutations. The type of death was apoptotic by several criteria, including induction by Fas, inhibition by the caspase inhibitor zVAD-fmk (zVal-Ala-Asp-fluoro-methyl ketone), activation of DEVDase activity (Asp-Glu-Val-Asp protease), specific cleavage of caspase-3, DNA fragmentation, and increased Annexin-V labeling. These data indicate that the most common and severe LHON pathogenic mutations 11778 and 3460 predispose cells to apoptosis, which may be relevant for the pathophysiology of cell death in LHON, and potential therapy.  (+info)

Identification of a gene locus for Senior-Loken syndrome in the region of the nephronophthisis type 3 gene. (4/183)

Senior-Loken syndrome is an autosomal recessive disease with the main features of nephronophthisis (NPH) and Leber congenital amaurosis. The gene for adolescent nephronophthisis (NPHP3) was recently localized to chromosome 3q21-q22. The hypothesis was tested that Senior-Loken syndrome (SLS) might localize to the same region by studying a kindred of German ancestry with extended consanguinity and typical findings of SLS. Twenty highly polymorphic markers located in the vicinity of the NPHP3 genetic region were tested. Haplotype analysis revealed homozygosity by descent in affected individuals, and linkage analysis yielded a parametric maximum multipoint logarithm of likelihood of odds (LOD) score of 3.14, thus identifying the first locus for SLS. The SLS1 locus is flanked by D3S1587 and D3S621 and contains a 14-cM interval that contains the whole critical NPHP3 region. Three additional families with SLS were studied, and evidence for genetic heterogeneity in one of them was found. Localization of a SLS locus to the region of NPHP3 opens the possibilities of both diseases arising by mutations within the same pleiotropic gene or two adjacent genes.  (+info)

Differentiation-specific effects of LHON mutations introduced into neuronal NT2 cells. (5/183)

Inheritance of one of three primary mutations at positions 11778, 3460 or 14484 of the mitochondrial genome in subunits of Complex I causes Leber's Hereditary Optic Neuropathy (LHON), a specific degeneration of the optic nerve, resulting in bilateral blindness. It has been unclear why inheritance of a systemic mitochondrial mutation would result in a specific neurodegeneration. To address the neuron-specific degenerative phenotype of the LHON genotype, we have created cybrids using a neuronal precursor cell line, Ntera 2/D1 (NT2), containing mitochondria from patient lymphoblasts bearing the most common LHON mutation (11778) and the most severe LHON mutation (3460). The undifferentiated LHON-NT2 mutant cells were not significantly different from the parental cell control in terms of mtDNA/nDNA ratio, mitochondrial membrane potential, reactive oxygen species (ROS) production or the ability to reduce Alamar Blue. Differentiation of NT2s resulted in a neuronal morphology and neuron-specific pattern of gene expression, and a 3-fold reduction in mtDNA/nDNA ratio in both mutant and control cells; however, the differentiation protocol yielded significantly less LHON cells than controls, by 30%, indicating either a decreased proliferative potential or increased cell death of the LHON-NT2 cells. Differentiation of the cells to the neuronal form also resulted in significant increases in ROS production in the LHON-NT2 neurons versus controls, which is abolished by rotenone, a specific inhibitor of Complex I. We infer that the LHON genotype requires a differentiated neuronal environment in order to induce increased mitochondrial ROS, which may be the cause of the reduced NT2 yield; and suggest that the LHON degenerative phenotype may be the result of an increase in mitochondrial superoxide which is caused by the LHON mutations, possibly mediated through neuron-specific alterations in Complex I structure.  (+info)

On the genetics of retinitis pigmentosa and on mutation-independent approaches to therapeutic intervention. (6/183)

Retinitis pigmentosa (RP), the group of hereditary conditions involving death of retinal photoreceptors, represents the most prevalent cause of visual handicap among working populations in developed countries. Here we provide an overview of the molecular pathologies associated with such disorders, from which it becomes clearly apparent that RP is one of the most genetically heterogeneous of hereditary conditions for which molecular pathologies have so far been elucidated. While heterogeneity of such magnitude would appear to represent a major impediment to the development of therapeutics, mutation-independent approaches to therapy are being developed to effectively by-pass such diversity in genetic aetiology. The implications of such technologies in terms of therapeutic intervention in RP, and indeed other genetically heterogeneous conditions, will be addressed.  (+info)

Recovery of visual functions in a mouse model of Leber congenital amaurosis. (7/183)

The visual process is initiated by the photoisomerization of 11-cis-retinal to all-trans-retinal. For sustained vision the 11-cis-chromophore must be regenerated from all-trans-retinal. This requires RPE65, a dominant retinal pigment epithelium protein. Disruption of the RPE65 gene results in massive accumulation of all-trans-retinyl esters in the retinal pigment epithelium, lack of 11-cis-retinal and therefore rhodopsin, and ultimately blindness. We reported previously (Van Hooser, J. P., Aleman, T. S., He, Y. G., Cideciyan, A. V., Kuksa, V., Pittler, S. J., Stone, E. M., Jacobson, S. G., and Palczewski, K. (2000) Proc. Natl. Acad. Sci. U. S. A. 97, 8623-8628) that in Rpe65-/- mice, oral administration of 9-cis-retinal generated isorhodopsin, a rod photopigment, and restored light sensitivity to the electroretinogram. Here, we provide evidence that early intervention by 9-cis-retinal administration significantly attenuated retinal ester accumulation and supported rod retinal function for more than 6 months post-treatment. In single cell recordings rod light sensitivity was shown to be a function of the amount of regenerated isorhodopsin; high doses restored rod responses with normal sensitivity and kinetics. Highly attenuated residual rod function was observed in untreated Rpe65-/- mice. This rod function is likely a consequence of low efficiency production of 11-cis-retinal by photo-conversion of all-trans-retinal in the retina as demonstrated by retinoid analysis. These studies show that pharmacological intervention produces long lasting preservation of visual function in dark-reared Rpe65-/- mice and may be a useful therapeutic strategy in recovering vision in humans diagnosed with Leber congenital amaurosis caused by mutations in the RPE65 gene, an inherited group of early onset blinding and retinal degenerations.  (+info)

Leber hereditary optic neuropathy. (8/183)

Leber hereditary optic neuropathy (LHON) is a mitochondrial genetic disease that preferentially causes blindness in young adult males, affecting about 1 in 25 000 of the British population. It is characterised by bilateral subacute loss of central vision owing to focal degeneration of the retinal ganglion cell layer and optic nerve. Over 95% of LHON cases are primarily the result of one of three mitochondrial DNA (mtDNA) point mutations, G3460A, G11778A, and T14484C, which all involve genes encoding complex I subunits of the respiratory chain. An intriguing feature of LHON is that only approximately 50% of males and approximately 10% of females who harbour a pathogenic mtDNA mutation actually develop the optic neuropathy. This marked incomplete penetrance and gender bias imply that additional mitochondrial and/or nuclear genetic factors must be modulating the phenotypic expression of LHON. It is also likely that environmental factors contribute to the onset of visual failure. However, these secondary precipitating factors remain poorly defined at present. In this review, we describe the natural history of this optic nerve disorder and highlight issues relating to clinical diagnosis, management, and genetic counselling. We also discuss the findings of recently published studies and the light they shed on the complex aetiology and pathophysiology of LHON.  (+info)

Optic atrophy is a medical term that refers to the degeneration and shrinkage (atrophy) of the optic nerve, which transmits visual information from the eye to the brain. This condition can result in various vision abnormalities, including loss of visual acuity, color vision deficiencies, and peripheral vision loss.

Optic atrophy can occur due to a variety of causes, such as:

* Traumatic injuries to the eye or optic nerve
* Glaucoma
* Optic neuritis (inflammation of the optic nerve)
* Ischemic optic neuropathy (reduced blood flow to the optic nerve)
* Compression or swelling of the optic nerve
* Hereditary or congenital conditions affecting the optic nerve
* Toxins and certain medications that can damage the optic nerve.

The diagnosis of optic atrophy typically involves a comprehensive eye examination, including visual acuity testing, refraction assessment, slit-lamp examination, and dilated funduscopic examination to evaluate the health of the optic nerve. In some cases, additional diagnostic tests such as visual field testing, optical coherence tomography (OCT), or magnetic resonance imaging (MRI) may be necessary to confirm the diagnosis and determine the underlying cause.

There is no specific treatment for optic atrophy, but addressing the underlying cause can help prevent further damage to the optic nerve. In some cases, vision rehabilitation may be recommended to help patients adapt to their visual impairment.

Autosomal dominant optic atrophy (ADOA) is a genetic disorder that affects the optic nerve, which transmits visual information from the eye to the brain. The term "optic atrophy" refers to degeneration or damage to the optic nerve. In ADOA, this condition is inherited in an autosomal dominant manner, meaning that only one copy of the mutated gene, located on one of the autosomal chromosomes (not a sex chromosome), needs to be present for the individual to develop the disorder.

The most common form of ADOA is caused by mutations in the OPA1 gene, which provides instructions for making a protein involved in the maintenance of mitochondria, the energy-producing structures in cells. The exact role of this protein in optic nerve function is not fully understood, but it is thought to play a critical role in maintaining the health and function of retinal ganglion cells, which are the neurons that make up the optic nerve.

In ADOA, mutations in the OPA1 gene lead to progressive degeneration of retinal ganglion cells and their axons (nerve fibers) within the optic nerve. This results in decreased visual acuity, color vision deficits, and a characteristic visual field defect called centrocecal scotoma, which is an area of blindness near the center of the visual field. The onset and severity of these symptoms can vary widely among individuals with ADOA.

It's important to note that medical definitions may contain complex terminology. In simpler terms, autosomal dominant optic atrophy (ADOA) is a genetic condition affecting the optic nerve, leading to decreased visual acuity and other vision problems due to degeneration of retinal ganglion cells. The disorder is inherited in an autosomal dominant manner, meaning only one copy of the mutated gene is needed for the individual to develop ADOA.

Hereditary optic atrophies (HOAs) are a group of genetic disorders that cause degeneration of the optic nerve, leading to vision loss. The optic nerve is responsible for transmitting visual information from the eye to the brain. In HOAs, this nerve degenerates over time, resulting in decreased visual acuity, color vision deficits, and sometimes visual field defects.

There are several types of HOAs, including dominant optic atrophy (DOA), Leber hereditary optic neuropathy (LHON), autosomal recessive optic atrophy (AROA), and Wolfram syndrome. Each type has a different inheritance pattern and is caused by mutations in different genes.

DOA is the most common form of HOA and is characterized by progressive vision loss that typically begins in childhood or early adulthood. It is inherited in an autosomal dominant manner, meaning that a child has a 50% chance of inheriting the disease-causing mutation from an affected parent.

LHON is a mitochondrial disorder that primarily affects males and is characterized by sudden, severe vision loss that typically occurs in young adulthood. It is caused by mutations in the mitochondrial DNA and is inherited maternally.

AROA is a rare form of HOA that is inherited in an autosomal recessive manner, meaning that both copies of the gene must be mutated to cause the disease. It typically presents in infancy or early childhood with progressive vision loss.

Wolfram syndrome is a rare genetic disorder that affects multiple organs, including the eyes, ears, and endocrine system. It is characterized by diabetes insipidus, diabetes mellitus, optic atrophy, and hearing loss. It is inherited in an autosomal recessive manner.

There is currently no cure for HOAs, but treatments such as low-vision aids and rehabilitation may help to manage the symptoms. Research is ongoing to develop new therapies for these disorders.

Hereditary Optic Atrophy, Leber type (LOA) is a mitochondrial DNA-associated inherited condition that primarily affects the optic nerve and leads to vision loss. It is characterized by the degeneration of retinal ganglion cells and their axons, which make up the optic nerve. This results in bilateral, painless, and progressive visual deterioration, typically beginning in young adulthood (14-35 years).

Leber's hereditary optic atrophy is caused by mutations in the mitochondrial DNA (mtDNA) gene MT-ND4 or MT-ND6. The condition follows a maternal pattern of inheritance, meaning that it is passed down through the mother's lineage.

The onset of LOA usually occurs in one eye first, followed by the second eye within weeks to months. Central vision is initially affected, leading to blurriness and loss of visual acuity. Color vision may also be impaired. The progression of the condition generally stabilizes after a few months, but complete recovery of vision is unlikely.

Currently, there is no cure for Leber's hereditary optic atrophy. Treatment focuses on managing symptoms and providing visual rehabilitation to help affected individuals adapt to their visual impairment.

Leber Congenital Amaurosis (LCA) is a group of inherited retinal degenerative disorders that affect the development and function of the retina, a light-sensitive tissue at the back of the eye. It is characterized by severe visual impairment or blindness from birth or early infancy.

The condition is caused by mutations in various genes involved in the normal functioning of photoreceptor cells (rods and cones) in the retina, which are responsible for capturing light and transmitting visual signals to the brain. As a result, the photoreceptors fail to develop properly or degenerate over time, leading to vision loss.

Symptoms of LCA may include roving eye movements (nystagmus), lack of fixation, decreased or absent response to light, and abnormal pupillary reflexes. Some individuals with LCA may also have other ocular abnormalities such as keratoconus, cataracts, or glaucoma.

LCA is typically inherited in an autosomal recessive manner, meaning that an individual must inherit two copies of the mutated gene (one from each parent) to develop the condition. Currently, there is no cure for LCA, but various treatments such as gene therapy and assistive devices may help improve visual function and quality of life for affected individuals.

Atrophy is a medical term that refers to the decrease in size and wasting of an organ or tissue due to the disappearance of cells, shrinkage of cells, or decreased number of cells. This process can be caused by various factors such as disuse, aging, degeneration, injury, or disease.

For example, if a muscle is immobilized for an extended period, it may undergo atrophy due to lack of use. Similarly, certain medical conditions like diabetes, cancer, and heart failure can lead to the wasting away of various tissues and organs in the body.

Atrophy can also occur as a result of natural aging processes, leading to decreased muscle mass and strength in older adults. In general, atrophy is characterized by a decrease in the volume or weight of an organ or tissue, which can have significant impacts on its function and overall health.

The optic nerve, also known as the second cranial nerve, is the nerve that transmits visual information from the retina to the brain. It is composed of approximately one million nerve fibers that carry signals related to vision, such as light intensity and color, from the eye's photoreceptor cells (rods and cones) to the visual cortex in the brain. The optic nerve is responsible for carrying this visual information so that it can be processed and interpreted by the brain, allowing us to see and perceive our surroundings. Damage to the optic nerve can result in vision loss or impairment.

Wolfram Syndrome is a rare, progressive, genetic disorder that affects multiple organ systems, particularly the eyes, brain, endocrine system, and hearing. It is characterized by the combination of several features including diabetes insipidus (DI), diabetes mellitus (DM), optic nerve atrophy, and various neurological symptoms. The onset of this syndrome typically occurs in childhood.

The two major types of Wolfram Syndrome are WFS1 and WFS2, with WFS1 being the most common form. They are caused by mutations in different genes (WFS1 and CISD2 respectively), both of which play a role in maintaining the health of cells in the body, particularly those in the pancreas, eyes, and ears.

The symptoms of Wolfram Syndrome can vary widely among affected individuals, but often include:
- Diabetes insipidus (DI): This is characterized by excessive thirst and urination due to problems with the body's regulation of fluids.
- Diabetes mellitus (DM): This type of diabetes results from issues with insulin production or usage, leading to high blood sugar levels.
- Optic nerve atrophy: This can cause vision loss, typically starting in early childhood and progressing over time.
- Neurological symptoms: These may include hearing loss, problems with balance and coordination, difficulty swallowing, and neuropsychiatric issues such as depression and anxiety.

Currently, there is no cure for Wolfram Syndrome, and treatment primarily focuses on managing the individual symptoms of the disorder.

The optic disk, also known as the optic nerve head, is the point where the optic nerve fibers exit the eye and transmit visual information to the brain. It appears as a pale, circular area in the back of the eye, near the center of the retina. The optic disk has no photoreceptor cells (rods and cones), so it is insensitive to light. It is an important structure to observe during eye examinations because changes in its appearance can indicate various ocular diseases or conditions, such as glaucoma, optic neuritis, or papilledema.

GTP (Guanosine Triphosphate) Phosphohydrolases are a group of enzymes that catalyze the hydrolysis of GTP to GDP (Guanosine Diphosphate) and inorganic phosphate. This reaction plays a crucial role in regulating various cellular processes, including signal transduction pathways, protein synthesis, and vesicle trafficking.

The human genome encodes several different types of GTP Phosphohydrolases, such as GTPase-activating proteins (GAPs), GTPase effectors, and G protein-coupled receptors (GPCRs). These enzymes share a common mechanism of action, in which they utilize the energy released from GTP hydrolysis to drive conformational changes that enable them to interact with downstream effector molecules and modulate their activity.

Dysregulation of GTP Phosphohydrolases has been implicated in various human diseases, including cancer, neurodegenerative disorders, and infectious diseases. Therefore, understanding the structure, function, and regulation of these enzymes is essential for developing novel therapeutic strategies to target these conditions.

Blindness is a condition of complete or near-complete vision loss. It can be caused by various factors such as eye diseases, injuries, or birth defects. Total blindness means that a person cannot see anything at all, while near-complete blindness refers to having only light perception or the ability to perceive the direction of light, but not able to discern shapes or forms. Legal blindness is a term used to define a certain level of visual impairment that qualifies an individual for government assistance and benefits; it usually means best corrected visual acuity of 20/200 or worse in the better eye, or a visual field no greater than 20 degrees in diameter.

Muscular atrophy is a condition characterized by a decrease in the size and mass of muscles due to lack of use, disease, or injury. This occurs when there is a disruption in the balance between muscle protein synthesis and degradation, leading to a net loss of muscle proteins. There are two main types of muscular atrophy:

1. Disuse atrophy: This type of atrophy occurs when muscles are not used or are immobilized for an extended period, such as after an injury, surgery, or prolonged bed rest. In this case, the nerves that control the muscles may still be functioning properly, but the muscles themselves waste away due to lack of use.
2. Neurogenic atrophy: This type of atrophy is caused by damage to the nerves that supply the muscles, leading to muscle weakness and wasting. Conditions such as amyotrophic lateral sclerosis (ALS), spinal cord injuries, and peripheral neuropathies can cause neurogenic atrophy.

In both cases, the affected muscles may become weak, shrink in size, and lose their tone and mass. Treatment for muscular atrophy depends on the underlying cause and may include physical therapy, exercise, and medication to manage symptoms and improve muscle strength and function.

Optic neuritis is a medical condition characterized by inflammation and damage to the optic nerve, which transmits visual information from the eye to the brain. This condition can result in various symptoms such as vision loss, pain with eye movement, color vision disturbances, and pupillary abnormalities. Optic neuritis may occur in isolation or be associated with other underlying medical conditions, including multiple sclerosis, neuromyelitis optica, and autoimmune disorders. The diagnosis typically involves a comprehensive eye examination, including visual acuity testing, dilated funduscopic examination, and possibly imaging studies like MRI to evaluate the optic nerve and brain. Treatment options may include corticosteroids or other immunomodulatory therapies to reduce inflammation and prevent further damage to the optic nerve.

Cis-trans isomeres are molecules that have the same molecular formula and skeletal structure, but differ in the arrangement of their atoms around a double bond. In a cis isomer, the two larger groups or atoms are on the same side of the double bond, while in a trans isomer, they are on opposite sides.

Cis-trans isomerases are enzymes that catalyze the interconversion between cis and trans isomers of various molecules, such as fatty acids, steroids, and retinals. These enzymes play important roles in various biological processes, including membrane fluidity, vision, and the biosynthesis of hormones and other signaling molecules.

Examples of cis-trans isomerases include:

* Fatty acid desaturases, which introduce double bonds into fatty acids and can convert trans isomers to cis isomers
* Retinal isomerases, which interconvert the cis and trans isomers of retinal, a molecule involved in vision
* Steroid isomerases, which catalyze the interconversion of various steroids, including cholesterol and its derivatives.

I must clarify that the term "pedigree" is not typically used in medical definitions. Instead, it is often employed in genetics and breeding, where it refers to the recorded ancestry of an individual or a family, tracing the inheritance of specific traits or diseases. In human genetics, a pedigree can help illustrate the pattern of genetic inheritance in families over multiple generations. However, it is not a medical term with a specific clinical definition.

Hereditary Sensory and Motor Neuropathy (HSMN) is a group of inherited disorders that affect the peripheral nerves, which are the nerves outside the brain and spinal cord. These nerves transmit information between the brain and muscles, as well as sensations such as touch, pain, heat, and cold.

HSMN is characterized by progressive degeneration of these peripheral nerves, leading to muscle weakness, numbness, and tingling sensations, particularly in the hands and feet. The condition can also affect the autonomic nervous system, which controls involuntary functions such as heart rate, blood pressure, and digestion.

HSMN is caused by genetic mutations that are inherited from one or both parents. There are several types of HSMN, each with its own specific symptoms, severity, and pattern of inheritance. The most common form is Charcot-Marie-Tooth disease (CMT), which affects both motor and sensory nerves.

Treatment for HSMN typically focuses on managing the symptoms and preventing complications. This may include physical therapy, bracing or orthopedic surgery to support weakened muscles, pain management, and lifestyle modifications such as avoiding activities that aggravate symptoms. There is currently no cure for HSMN, but ongoing research is aimed at developing new treatments and therapies to slow or halt the progression of the disease.

The optic chiasm is a structure in the brain where the optic nerves from each eye meet and cross. This allows for the integration of visual information from both eyes into the brain's visual cortex, creating a single, combined image of the visual world. The optic chiasm plays an important role in the processing of visual information and helps to facilitate depth perception and other complex visual tasks. Damage to the optic chiasm can result in various visual field deficits, such as bitemporal hemianopsia, where there is a loss of vision in the outer halves (temporal fields) of both eyes' visual fields.

Mitochondrial DNA (mtDNA) is the genetic material present in the mitochondria, which are specialized structures within cells that generate energy. Unlike nuclear DNA, which is present in the cell nucleus and inherited from both parents, mtDNA is inherited solely from the mother.

MtDNA is a circular molecule that contains 37 genes, including 13 genes that encode for proteins involved in oxidative phosphorylation, a process that generates energy in the form of ATP. The remaining genes encode for rRNAs and tRNAs, which are necessary for protein synthesis within the mitochondria.

Mutations in mtDNA can lead to a variety of genetic disorders, including mitochondrial diseases, which can affect any organ system in the body. These mutations can also be used in forensic science to identify individuals and establish biological relationships.

Retinal Ganglion Cells (RGCs) are a type of neuron located in the innermost layer of the retina, the light-sensitive tissue at the back of the eye. These cells receive visual information from photoreceptors (rods and cones) via intermediate cells called bipolar cells. RGCs then send this visual information through their long axons to form the optic nerve, which transmits the signals to the brain for processing and interpretation as vision.

There are several types of RGCs, each with distinct morphological and functional characteristics. Some RGCs are specialized in detecting specific features of the visual scene, such as motion, contrast, color, or brightness. The diversity of RGCs allows for a rich and complex representation of the visual world in the brain.

Damage to RGCs can lead to various visual impairments, including loss of vision, reduced visual acuity, and altered visual fields. Conditions associated with RGC damage or degeneration include glaucoma, optic neuritis, ischemic optic neuropathy, and some inherited retinal diseases.

Papilledema is a medical term that refers to swelling of the optic nerve head, also known as the disc, which is the point where the optic nerve enters the back of the eye (the retina). This swelling can be caused by increased pressure within the skull, such as from brain tumors, meningitis, or idiopathic intracranial hypertension. Papilledema is usually detected through a routine eye examination and may be accompanied by symptoms such as headaches, visual disturbances, and nausea. If left untreated, papilledema can lead to permanent vision loss.

Vision disorders refer to a wide range of conditions that affect the visual system and result in various symptoms, such as blurry vision, double vision, distorted vision, impaired depth perception, and difficulty with visual tracking or focusing. These disorders can be categorized into several types, including:

1. Refractive errors: These occur when the shape of the eye prevents light from focusing directly on the retina, resulting in blurry vision. Examples include myopia (nearsightedness), hyperopia (farsightedness), astigmatism, and presbyopia (age-related loss of near vision).
2. Strabismus: Also known as crossed eyes or walleye, strabismus is a misalignment of the eyes where they point in different directions, which can lead to double vision or loss of depth perception.
3. Amblyopia: Often called lazy eye, amblyopia is a condition where one eye has reduced vision due to lack of proper visual development during childhood. It may be caused by strabismus, refractive errors, or other factors that interfere with normal visual development.
4. Accommodative disorders: These involve problems with the focusing ability of the eyes, such as convergence insufficiency (difficulty focusing on close objects) and accommodative dysfunction (inability to maintain clear vision at different distances).
5. Binocular vision disorders: These affect how the eyes work together as a team, leading to issues like poor depth perception, eye strain, and headaches. Examples include convergence insufficiency, divergence excess, and suppression.
6. Ocular motility disorders: These involve problems with eye movement, such as nystagmus (involuntary eye movements), strabismus, or restricted extraocular muscle function.
7. Visual processing disorders: These affect the brain's ability to interpret and make sense of visual information, even when the eyes themselves are healthy. Symptoms may include difficulty with reading, recognizing shapes and objects, and understanding spatial relationships.
8. Low vision: This term refers to significant visual impairment that cannot be fully corrected with glasses, contact lenses, medication, or surgery. It includes conditions like macular degeneration, diabetic retinopathy, glaucoma, and cataracts.
9. Blindness: Complete loss of sight in both eyes, which can be caused by various factors such as injury, disease, or genetic conditions.

Electroretinography (ERG) is a medical test used to evaluate the functioning of the retina, which is the light-sensitive tissue located at the back of the eye. The test measures the electrical responses of the retina to light stimulation.

During the procedure, a special contact lens or electrode is placed on the surface of the eye to record the electrical activity generated by the retina's light-sensitive cells (rods and cones) and other cells in the retina. The test typically involves presenting different levels of flashes of light to the eye while the electrical responses are recorded.

The resulting ERG waveform provides information about the overall health and function of the retina, including the condition of the photoreceptors, the integrity of the inner retinal layers, and the health of the retinal ganglion cells. This test is often used to diagnose and monitor various retinal disorders, such as retinitis pigmentosa, macular degeneration, and diabetic retinopathy.

Visual acuity is a measure of the sharpness or clarity of vision. It is usually tested by reading an eye chart from a specific distance, such as 20 feet (6 meters). The standard eye chart used for this purpose is called the Snellen chart, which contains rows of letters that decrease in size as you read down the chart.

Visual acuity is typically expressed as a fraction, with the numerator representing the testing distance and the denominator indicating the smallest line of type that can be read clearly. For example, if a person can read the line on the eye chart that corresponds to a visual acuity of 20/20, it means they have normal vision at 20 feet. If their visual acuity is 20/40, it means they must be as close as 20 feet to see what someone with normal vision can see at 40 feet.

It's important to note that visual acuity is just one aspect of overall vision and does not necessarily reflect other important factors such as peripheral vision, depth perception, color vision, or contrast sensitivity.

Optic nerve injuries refer to damages or trauma inflicted on the optic nerve, which is a crucial component of the visual system. The optic nerve transmits visual information from the retina to the brain, enabling us to see. Injuries to the optic nerve can result in various visual impairments, including partial or complete vision loss, decreased visual acuity, changes in color perception, and reduced field of view.

These injuries may occur due to several reasons, such as:

1. Direct trauma to the eye or head
2. Increased pressure inside the eye (glaucoma)
3. Optic neuritis, an inflammation of the optic nerve
4. Ischemia, or insufficient blood supply to the optic nerve
5. Compression from tumors or other space-occupying lesions
6. Intrinsic degenerative conditions affecting the optic nerve
7. Toxic exposure to certain chemicals or medications

Optic nerve injuries are diagnosed through a comprehensive eye examination, including visual acuity testing, slit-lamp examination, dilated fundus exam, and additional diagnostic tests like optical coherence tomography (OCT) and visual field testing. Treatment options vary depending on the cause and severity of the injury but may include medications, surgery, or vision rehabilitation.

The retina is the innermost, light-sensitive layer of tissue in the eye of many vertebrates and some cephalopods. It receives light that has been focused by the cornea and lens, converts it into neural signals, and sends these to the brain via the optic nerve. The retina contains several types of photoreceptor cells including rods (which handle vision in low light) and cones (which are active in bright light and are capable of color vision).

In medical terms, any pathological changes or diseases affecting the retinal structure and function can lead to visual impairment or blindness. Examples include age-related macular degeneration, diabetic retinopathy, retinal detachment, and retinitis pigmentosa among others.

Spinal muscular atrophy (SMA) is a genetic disorder that affects the motor neurons in the spinal cord, leading to muscle weakness and atrophy. It is caused by a mutation in the survival motor neuron 1 (SMN1) gene, which results in a deficiency of SMN protein necessary for the survival of motor neurons.

There are several types of SMA, classified based on the age of onset and severity of symptoms. The most common type is type 1, also known as Werdnig-Hoffmann disease, which presents in infancy and is characterized by severe muscle weakness, hypotonia, and feeding difficulties. Other types include type 2 (intermediate SMA), type 3 (Kugelberg-Welander disease), and type 4 (adult-onset SMA).

The symptoms of SMA may include muscle wasting, fasciculations, weakness, hypotonia, respiratory difficulties, and mobility impairment. The diagnosis of SMA typically involves genetic testing to confirm the presence of a mutation in the SMN1 gene. Treatment options for SMA may include medications, physical therapy, assistive devices, and respiratory support.

A mutation is a permanent change in the DNA sequence of an organism's genome. Mutations can occur spontaneously or be caused by environmental factors such as exposure to radiation, chemicals, or viruses. They may have various effects on the organism, ranging from benign to harmful, depending on where they occur and whether they alter the function of essential proteins. In some cases, mutations can increase an individual's susceptibility to certain diseases or disorders, while in others, they may confer a survival advantage. Mutations are the driving force behind evolution, as they introduce new genetic variability into populations, which can then be acted upon by natural selection.

DNA Mutational Analysis is a laboratory test used to identify genetic variations or changes (mutations) in the DNA sequence of a gene. This type of analysis can be used to diagnose genetic disorders, predict the risk of developing certain diseases, determine the most effective treatment for cancer, or assess the likelihood of passing on an inherited condition to offspring.

The test involves extracting DNA from a patient's sample (such as blood, saliva, or tissue), amplifying specific regions of interest using polymerase chain reaction (PCR), and then sequencing those regions to determine the precise order of nucleotide bases in the DNA molecule. The resulting sequence is then compared to reference sequences to identify any variations or mutations that may be present.

DNA Mutational Analysis can detect a wide range of genetic changes, including single-nucleotide polymorphisms (SNPs), insertions, deletions, duplications, and rearrangements. The test is often used in conjunction with other diagnostic tests and clinical evaluations to provide a comprehensive assessment of a patient's genetic profile.

It is important to note that not all mutations are pathogenic or associated with disease, and the interpretation of DNA Mutational Analysis results requires careful consideration of the patient's medical history, family history, and other relevant factors.

Eye proteins, also known as ocular proteins, are specific proteins that are found within the eye and play crucial roles in maintaining proper eye function and health. These proteins can be found in various parts of the eye, including the cornea, iris, lens, retina, and other structures. They perform a wide range of functions, such as:

1. Structural support: Proteins like collagen and elastin provide strength and flexibility to the eye's tissues, enabling them to maintain their shape and withstand mechanical stress.
2. Light absorption and transmission: Proteins like opsins and crystallins are involved in capturing and transmitting light signals within the eye, which is essential for vision.
3. Protection against damage: Some eye proteins, such as antioxidant enzymes and heat shock proteins, help protect the eye from oxidative stress, UV radiation, and other environmental factors that can cause damage.
4. Regulation of eye growth and development: Various growth factors and signaling molecules, which are protein-based, contribute to the proper growth, differentiation, and maintenance of eye tissues during embryonic development and throughout adulthood.
5. Immune defense: Proteins involved in the immune response, such as complement components and immunoglobulins, help protect the eye from infection and inflammation.
6. Maintenance of transparency: Crystallin proteins in the lens maintain its transparency, allowing light to pass through unobstructed for clear vision.
7. Neuroprotection: Certain eye proteins, like brain-derived neurotrophic factor (BDNF), support the survival and function of neurons within the retina, helping to preserve vision.

Dysfunction or damage to these eye proteins can contribute to various eye disorders and diseases, such as cataracts, age-related macular degeneration, glaucoma, diabetic retinopathy, and others.

Recessive genes refer to the alleles (versions of a gene) that will only be expressed when an individual has two copies of that particular allele, one inherited from each parent. If an individual inherits one recessive allele and one dominant allele for a particular gene, the dominant allele will be expressed and the recessive allele will have no effect on the individual's phenotype (observable traits).

Recessive genes can still play a role in determining an individual's genetic makeup and can be passed down through generations even if they are not expressed. If two carriers of a recessive gene have children, there is a 25% chance that their offspring will inherit two copies of the recessive allele and exhibit the associated recessive trait.

Examples of genetic disorders caused by recessive genes include cystic fibrosis, sickle cell anemia, and albinism.

Onchocerciasis, Ocular is a medical condition that specifically refers to the eye manifestations caused by the parasitic infection, Onchocerca volvulus. Also known as "river blindness," this disease is spread through the bite of infected blackflies.

Ocular onchocerciasis affects various parts of the eye, including the conjunctiva, cornea, iris, and retina. The infection can cause symptoms such as itching, burning, and redness of the eyes. Over time, it may lead to more serious complications like punctate keratitis (small, scattered opacities on the cornea), cataracts, glaucoma, and ultimately, blindness.

The infection is diagnosed through a skin snip or blood test, which can detect the presence of microfilariae (the larval stage of the parasite) or antibodies against the parasite. Treatment typically involves administering oral medications such as ivermectin, which kills the microfilariae and reduces the risk of eye damage. However, it does not kill the adult worms, so multiple doses are often required to control the infection. In some cases, surgery may be necessary to remove advanced ocular lesions.

Eye diseases are a range of conditions that affect the eye or visual system, causing damage to vision and, in some cases, leading to blindness. These diseases can be categorized into various types, including:

1. Refractive errors: These include myopia (nearsightedness), hyperopia (farsightedness), astigmatism, and presbyopia, which affect the way light is focused on the retina and can usually be corrected with glasses or contact lenses.
2. Cataracts: A clouding of the lens inside the eye that leads to blurry vision, glare, and decreased contrast sensitivity. Cataract surgery is the most common treatment for this condition.
3. Glaucoma: A group of diseases characterized by increased pressure in the eye, leading to damage to the optic nerve and potential blindness if left untreated. Treatment includes medications, laser therapy, or surgery.
4. Age-related macular degeneration (AMD): A progressive condition that affects the central part of the retina called the macula, causing blurry vision and, in advanced stages, loss of central vision. Treatment may include anti-VEGF injections, laser therapy, or nutritional supplements.
5. Diabetic retinopathy: A complication of diabetes that affects the blood vessels in the retina, leading to bleeding, leakage, and potential blindness if left untreated. Treatment includes laser therapy, anti-VEGF injections, or surgery.
6. Retinal detachment: A separation of the retina from its underlying tissue, which can lead to vision loss if not treated promptly with surgery.
7. Amblyopia (lazy eye): A condition where one eye does not develop normal vision, often due to a misalignment or refractive error in childhood. Treatment includes correcting the underlying problem and encouraging the use of the weaker eye through patching or other methods.
8. Strabismus (crossed eyes): A misalignment of the eyes that can lead to amblyopia if not treated promptly with surgery, glasses, or other methods.
9. Corneal diseases: Conditions that affect the transparent outer layer of the eye, such as keratoconus, Fuchs' dystrophy, and infectious keratitis, which can lead to vision loss if not treated promptly.
10. Uveitis: Inflammation of the middle layer of the eye, which can cause vision loss if not treated promptly with anti-inflammatory medications or surgery.

Mitochondrial diseases are a group of disorders caused by dysfunctions in the mitochondria, which are the energy-producing structures in cells. These diseases can affect people of any age and can manifest in various ways, depending on which organs or systems are affected. Common symptoms include muscle weakness, neurological problems, cardiac disease, diabetes, and vision/hearing loss. Mitochondrial diseases can be inherited from either the mother's or father's side, or they can occur spontaneously due to genetic mutations. They can range from mild to severe and can even be life-threatening in some cases.

NADH dehydrogenase, also known as Complex I, is an enzyme complex in the electron transport chain located in the inner mitochondrial membrane. It catalyzes the oxidation of NADH to NAD+ and the reduction of coenzyme Q to ubiquinol, playing a crucial role in cellular respiration and energy production. The reaction involves the transfer of electrons from NADH to coenzyme Q, which contributes to the generation of a proton gradient across the membrane, ultimately leading to ATP synthesis. Defects in NADH dehydrogenase can result in various mitochondrial diseases and disorders.

The optic lobe in non-mammals refers to a specific region of the brain that is responsible for processing visual information. It is a part of the protocerebrum in the insect brain and is analogous to the mammalian visual cortex. The optic lobes receive input directly from the eyes via the optic nerves and are involved in the interpretation and integration of visual stimuli, enabling non-mammals to perceive and respond to their environment. In some invertebrates, like insects, the optic lobe is further divided into subregions, including the lamina, medulla, and lobula, each with distinct functions in visual processing.

Retinal degeneration is a broad term that refers to the progressive loss of photoreceptor cells (rods and cones) in the retina, which are responsible for converting light into electrical signals that are sent to the brain. This process can lead to vision loss or blindness. There are many different types of retinal degeneration, including age-related macular degeneration, retinitis pigmentosa, and Stargardt's disease, among others. These conditions can have varying causes, such as genetic mutations, environmental factors, or a combination of both. Treatment options vary depending on the specific type and progression of the condition.

Ischemic optic neuropathy (ION) is a medical condition that refers to the damage or death of the optic nerve due to insufficient blood supply. The optic nerve is responsible for transmitting visual information from the eye to the brain.

In ION, the blood vessels that supply the optic nerve become blocked or narrowed, leading to decreased blood flow and oxygen delivery to the nerve fibers. This results in inflammation, swelling, and ultimately, damage to the optic nerve. The damage can cause sudden, painless vision loss, often noticed upon waking up in the morning.

There are two types of ION: anterior ischemic optic neuropathy (AION) and posterior ischemic optic neuropathy (PION). AION affects the front part of the optic nerve, while PION affects the back part of the nerve. AION is further classified into arteritic and non-arteritic types, depending on whether it is caused by giant cell arteritis or not.

Risk factors for ION include age (most commonly occurring in people over 50), hypertension, diabetes, smoking, sleep apnea, and other cardiovascular diseases. Treatment options depend on the type and cause of ION and may include controlling underlying medical conditions, administering corticosteroids, or undergoing surgical procedures to improve blood flow.

Multiple System Atrophy (MSA) is a rare, progressive neurodegenerative disorder that affects multiple systems in the body. It is characterized by a combination of symptoms including Parkinsonism (such as stiffness, slowness of movement, and tremors), cerebellar ataxia (lack of muscle coordination), autonomic dysfunction (problems with the autonomic nervous system which controls involuntary actions like heart rate, blood pressure, sweating, and digestion), and pyramidal signs (abnormalities in the corticospinal tracts that control voluntary movements).

The disorder is caused by the degeneration of nerve cells in various parts of the brain and spinal cord, leading to a loss of function in these areas. The exact cause of MSA is unknown, but it is thought to involve a combination of genetic and environmental factors. There is currently no cure for MSA, and treatment is focused on managing symptoms and improving quality of life.

Glutarates are compounds that contain a glutaric acid group. Glutaric acid is a carboxylic acid with a five-carbon chain and two carboxyl groups at the 1st and 5th carbon positions. Glutarates can be found in various substances, including certain foods and medications.

In a medical context, glutarates are sometimes used as ingredients in pharmaceutical products. For example, sodium phenylbutyrate, which is a salt of phenylbutyric acid and butyric acid, contains a glutaric acid group and is used as a medication to treat urea cycle disorders.

Glutarates can also be found in some metabolic pathways in the body, where they play a role in energy production and other biochemical processes. However, abnormal accumulation of glutaric acid or its derivatives can lead to certain medical conditions, such as glutaric acidemia type I, which is an inherited disorder of metabolism that can cause neurological symptoms and other health problems.

Optic flow is not a medical term per se, but rather a term used in the field of visual perception and neuroscience. It refers to the pattern of motion of objects in the visual field that occurs as an observer moves through the environment. This pattern of motion is important for the perception of self-motion and the estimation of egocentric distance (the distance of objects in the environment relative to the observer). Optic flow has been studied in relation to various clinical populations, such as individuals with vestibular disorders or visual impairments, who may have difficulty processing optic flow information.

Visual fields refer to the total area in which objects can be seen while keeping the eyes focused on a central point. It is the entire area that can be observed using peripheral (side) vision while the eye gazes at a fixed point. A visual field test is used to detect blind spots or gaps (scotomas) in a person's vision, which could indicate various medical conditions such as glaucoma, retinal damage, optic nerve disease, brain tumors, or strokes. The test measures both the central and peripheral vision and maps the entire area that can be seen when focusing on a single point.

"Fundus Oculi" is a medical term that refers to the back part of the interior of the eye, including the optic disc, macula, fovea, retinal vasculature, and peripheral retina. It is the area where light is focused and then transmitted to the brain via the optic nerve, forming visual images. Examinations of the fundus oculi are crucial for detecting various eye conditions such as diabetic retinopathy, macular degeneration, glaucoma, and other retinal diseases. The examination is typically performed using an ophthalmoscope or a specialized camera called a retinal camera.

Consanguinity is a medical and genetic term that refers to the degree of genetic relationship between two individuals who share common ancestors. Consanguineous relationships exist when people are related by blood, through a common ancestor or siblings who have children together. The closer the relationship between the two individuals, the higher the degree of consanguinity.

The degree of consanguinity is typically expressed as a percentage or fraction, with higher values indicating a closer genetic relationship. For example, first-degree relatives, such as parents and children or full siblings, share approximately 50% of their genes and have a consanguinity coefficient of 0.25 (or 25%).

Consanguinity can increase the risk of certain genetic disorders and birth defects in offspring due to the increased likelihood of sharing harmful recessive genes. The risks depend on the degree of consanguinity, with closer relationships carrying higher risks. It is important for individuals who are planning to have children and have a history of consanguinity to consider genetic counseling and testing to assess their risk of passing on genetic disorders.

A missense mutation is a type of point mutation in which a single nucleotide change results in the substitution of a different amino acid in the protein that is encoded by the affected gene. This occurs when the altered codon (a sequence of three nucleotides that corresponds to a specific amino acid) specifies a different amino acid than the original one. The function and/or stability of the resulting protein may be affected, depending on the type and location of the missense mutation. Missense mutations can have various effects, ranging from benign to severe, depending on the importance of the changed amino acid for the protein's structure or function.

Diabetes Insipidus is a medical condition characterized by the excretion of large amounts of dilute urine (polyuria) and increased thirst (polydipsia). It is caused by a deficiency in the hormone vasopressin (also known as antidiuretic hormone or ADH), which regulates the body's water balance.

In normal physiology, vasopressin is released from the posterior pituitary gland in response to an increase in osmolality of the blood or a decrease in blood volume. This causes the kidneys to retain water and concentrate the urine. In Diabetes Insipidus, there is either a lack of vasopressin production (central diabetes insipidus) or a decreased response to vasopressin by the kidneys (nephrogenic diabetes insipidus).

Central Diabetes Insipidus can be caused by damage to the hypothalamus or pituitary gland, such as from tumors, trauma, or surgery. Nephrogenic Diabetes Insipidus can be caused by genetic factors, kidney disease, or certain medications that interfere with the action of vasopressin on the kidneys.

Treatment for Diabetes Insipidus depends on the underlying cause. In central diabetes insipidus, desmopressin, a synthetic analogue of vasopressin, can be administered to replace the missing hormone. In nephrogenic diabetes insipidus, treatment may involve addressing the underlying kidney disease or adjusting medications that interfere with vasopressin action. It is important for individuals with Diabetes Insipidus to maintain adequate hydration and monitor their fluid intake and urine output.

A nonsense codon is a sequence of three nucleotides in DNA or RNA that does not code for an amino acid. Instead, it signals the end of the protein-coding region of a gene and triggers the termination of translation, the process by which the genetic code is translated into a protein.

In DNA, the nonsense codons are UAA, UAG, and UGA, which are also known as "stop codons." When these codons are encountered during translation, they cause the release of the newly synthesized polypeptide chain from the ribosome, bringing the process of protein synthesis to a halt.

Nonsense mutations are changes in the DNA sequence that result in the appearance of a nonsense codon where an amino acid-coding codon used to be. These types of mutations can lead to premature termination of translation and the production of truncated, nonfunctional proteins, which can cause genetic diseases or contribute to cancer development.

Mitochondrial dynamics refer to the processes that regulate the shape, size, distribution, and quality control of mitochondria within cells. These dynamic processes include:

1. Mitochondrial Fusion: This is the process by which two adjacent mitochondria merge together to form a single, elongated organelle. Fusion allows for the exchange of mitochondrial content, including DNA, proteins, and metabolites, which helps maintain genetic stability and promote bioenergetic efficiency.
2. Mitochondrial Fission: This is the process by which a single mitochondrion divides into two separate organelles. Fission plays a crucial role in mitochondrial division, inheritance, and quality control, as it enables the segregation of damaged or dysfunctional mitochondria for degradation via autophagy (mitophagy).
3. Mitochondrial Transport: This is the active movement of mitochondria within cells, facilitated by cytoskeletal motor proteins. Mitochondrial transport enables organelles to be distributed evenly throughout the cell and to reach specific subcellular locations where their energy demands are high.
4. Mitochondrial Dynamics Regulation: The regulation of mitochondrial dynamics involves a complex interplay between various proteins, lipids, and signaling pathways that control fusion, fission, transport, and quality control processes. These regulatory mechanisms help maintain the balance between mitochondrial biogenesis (the generation of new organelles) and mitophagy (the removal of damaged ones), ensuring proper cellular homeostasis and function.

Dysregulation of mitochondrial dynamics has been implicated in various pathological conditions, including neurodegenerative diseases, metabolic disorders, and aging-related processes.

Myoclonic cerebellar dyssynergia is not a widely recognized or formally defined medical term. However, based on its individual components, it can be inferred to refer to a neurological condition characterized by:

1. Myoclonus: These are sudden, involuntary jerking movements of a muscle or group of muscles. They typically occur as a result of hyperexcitability of the neurons in the brain that control movement (motor neurons).
2. Cerebellar: The cerebellum is a part of the brain responsible for coordinating muscle movements, maintaining posture and balance, and fine-tuning motor skills. When a condition is described as "cerebellar," it implies that there is some dysfunction or abnormality in this region of the brain.
3. Dyssynergia: This term refers to a lack of coordination between muscles and muscle groups during voluntary movements. It can result from damage to the cerebellum or other parts of the nervous system involved in motor control.

Therefore, myoclonic cerebellar dyssynergia could be interpreted as a condition characterized by involuntary muscle jerks (myoclonus) and impaired coordination of voluntary movements (dyssynergia), likely due to cerebellar dysfunction. However, it is essential to consult with a medical professional for an accurate diagnosis and treatment plan if you or someone else experiences symptoms that may align with this description.

Low vision is a term used to describe significant visual impairment that cannot be corrected with standard glasses, contact lenses, medication or surgery. It is typically defined as visual acuity of less than 20/70 in the better-seeing eye after best correction, or a visual field of less than 20 degrees in the better-seeing eye.

People with low vision may have difficulty performing everyday tasks such as reading, recognizing faces, watching television, driving, or simply navigating their environment. They may also experience symptoms such as sensitivity to light, glare, or contrast, and may benefit from the use of visual aids, assistive devices, and rehabilitation services to help them maximize their remaining vision and maintain their independence.

Low vision can result from a variety of causes, including eye diseases such as macular degeneration, diabetic retinopathy, glaucoma, or cataracts, as well as congenital or inherited conditions, brain injuries, or aging. It is important for individuals with low vision to receive regular eye examinations and consult with a low vision specialist to determine the best course of treatment and management.

Mitochondrial proteins are any proteins that are encoded by the nuclear genome or mitochondrial genome and are located within the mitochondria, an organelle found in eukaryotic cells. These proteins play crucial roles in various cellular processes including energy production, metabolism of lipids, amino acids, and steroids, regulation of calcium homeostasis, and programmed cell death or apoptosis.

Mitochondrial proteins can be classified into two main categories based on their origin:

1. Nuclear-encoded mitochondrial proteins (NEMPs): These are proteins that are encoded by genes located in the nucleus, synthesized in the cytoplasm, and then imported into the mitochondria through specific import pathways. NEMPs make up about 99% of all mitochondrial proteins and are involved in various functions such as oxidative phosphorylation, tricarboxylic acid (TCA) cycle, fatty acid oxidation, and mitochondrial dynamics.

2. Mitochondrial DNA-encoded proteins (MEPs): These are proteins that are encoded by the mitochondrial genome, synthesized within the mitochondria, and play essential roles in the electron transport chain (ETC), a key component of oxidative phosphorylation. The human mitochondrial genome encodes only 13 proteins, all of which are subunits of complexes I, III, IV, and V of the ETC.

Defects in mitochondrial proteins can lead to various mitochondrial disorders, which often manifest as neurological, muscular, or metabolic symptoms due to impaired energy production. These disorders are usually caused by mutations in either nuclear or mitochondrial genes that encode mitochondrial proteins.

A syndrome, in medical terms, is a set of symptoms that collectively indicate or characterize a disease, disorder, or underlying pathological process. It's essentially a collection of signs and/or symptoms that frequently occur together and can suggest a particular cause or condition, even though the exact physiological mechanisms might not be fully understood.

For example, Down syndrome is characterized by specific physical features, cognitive delays, and other developmental issues resulting from an extra copy of chromosome 21. Similarly, metabolic syndromes like diabetes mellitus type 2 involve a group of risk factors such as obesity, high blood pressure, high blood sugar, and abnormal cholesterol or triglyceride levels that collectively increase the risk of heart disease, stroke, and diabetes.

It's important to note that a syndrome is not a specific diagnosis; rather, it's a pattern of symptoms that can help guide further diagnostic evaluation and management.

Spinal muscular atrophies (SMAs) of childhood are a group of inherited neuromuscular disorders characterized by degeneration and loss of lower motor neurons in the spinal cord, leading to progressive muscle weakness and atrophy. The severity and age of onset can vary significantly, with some forms presenting in infancy and others in later childhood or even adulthood.

The most common form of SMA is 5q autosomal recessive SMA, also known as survival motor neuron (SMN) disease, which results from mutations in the SMN1 gene. The severity of this form can range from severe (type I or Werdnig-Hoffmann disease), intermediate (type II or chronic infantile neurodegenerative disorder), to mild (type III or Kugelberg-Welander disease).

Type I SMA is the most severe form, with onset before 6 months of age and rapid progression leading to death within the first two years of life if left untreated. Type II SMA has an onset between 6 and 18 months of age, with affected children never achieving the ability to walk independently. Type III SMA has a later onset, typically after 18 months of age, and is characterized by a slower progression, allowing for the ability to walk unaided, although mobility may be lost over time.

Other forms of childhood-onset SMA include autosomal dominant distal SMA, X-linked SMA, and spinal bulbar muscular atrophy (SBMA or Kennedy's disease). These forms have distinct genetic causes and clinical presentations.

In general, SMAs are characterized by muscle weakness, hypotonia, fasciculations, tongue atrophy, and depressed or absent deep tendon reflexes. Respiratory and nutritional support is often required in more severe cases. Recent advances in gene therapy have led to the development of disease-modifying treatments for some forms of SMA.

Mitochondria are specialized structures located inside cells that convert the energy from food into ATP (adenosine triphosphate), which is the primary form of energy used by cells. They are often referred to as the "powerhouses" of the cell because they generate most of the cell's supply of chemical energy. Mitochondria are also involved in various other cellular processes, such as signaling, differentiation, and apoptosis (programmed cell death).

Mitochondria have their own DNA, known as mitochondrial DNA (mtDNA), which is inherited maternally. This means that mtDNA is passed down from the mother to her offspring through the egg cells. Mitochondrial dysfunction has been linked to a variety of diseases and conditions, including neurodegenerative disorders, diabetes, and aging.

I'm sorry for any confusion, but "Optics and Photonics" is a broad field that encompasses various scientific and engineering disciplines. It doesn't have a specific medical definition, as it's not a term typically used in a medical context.

However, I can provide a general definition:

Optics is the study of light and its interactions with matter. This includes how light is produced, controlled, transmitted, and detected. It involves phenomena such as reflection, refraction, diffraction, and interference.

Photonics, on the other hand, is a branch of optics that deals with the generation, detection, and manipulation of individual photons, the basic units of light. Photonics is often applied to technologies such as lasers, fiber optics, and optical communications.

In a medical context, these fields might be used in various diagnostic and therapeutic applications, such as endoscopes, ophthalmic devices, laser surgery, and imaging technologies like MRI and CT scans. But the terms "Optics" and "Photonics" themselves are not medical conditions or treatments.

Microcephaly is a medical condition where an individual has a smaller than average head size. The circumference of the head is significantly below the normal range for age and sex. This condition is typically caused by abnormal brain development, which can be due to genetic factors or environmental influences such as infections or exposure to harmful substances during pregnancy.

Microcephaly can be present at birth (congenital) or develop in the first few years of life. People with microcephaly often have intellectual disabilities, delayed development, and other neurological problems. However, the severity of these issues can vary widely, ranging from mild to severe. It is important to note that not all individuals with microcephaly will experience significant impairments or challenges.

A photoreceptor connecting cilium, also known as the connecting cilium or the outer segment initial segment, is a specialized structure found in the eye's photoreceptor cells (rods and cones). It is a thin, non-motile cilium that connects the inner segment of the photoreceptor cell to the outer segment. The outer segment contains the visual pigments that absorb light and initiate the process of vision.

The connecting cilium plays a crucial role in the maintenance and function of the outer segment by providing a passageway for the transport of proteins, lipids, and other molecules from the inner segment to the outer segment. This process is essential for the renewal and turnover of the visual pigments and other components of the outer segment. The connecting cilium also helps maintain the structural integrity of the photoreceptor cells and their sensitivity to light.

Defects in the connecting cilium can lead to various retinal disorders, such as retinitis pigmentosa and Leber congenital amaurosis, which are characterized by progressive vision loss due to the degeneration of the photoreceptor cells.

Retinal diseases refer to a group of conditions that affect the retina, which is the light-sensitive tissue located at the back of the eye. The retina is responsible for converting light into electrical signals that are sent to the brain and interpreted as visual images. Retinal diseases can cause vision loss or even blindness, depending on their severity and location in the retina.

Some common retinal diseases include:

1. Age-related macular degeneration (AMD): A progressive disease that affects the central part of the retina called the macula, causing blurred or distorted vision.
2. Diabetic retinopathy: A complication of diabetes that can damage the blood vessels in the retina, leading to vision loss.
3. Retinal detachment: A serious condition where the retina becomes separated from its underlying tissue, requiring immediate medical attention.
4. Macular edema: Swelling or thickening of the macula due to fluid accumulation, which can cause blurred vision.
5. Retinitis pigmentosa: A group of inherited eye disorders that affect the retina's ability to respond to light, causing progressive vision loss.
6. Macular hole: A small break in the macula that can cause distorted or blurry vision.
7. Retinal vein occlusion: Blockage of the retinal veins that can lead to bleeding, swelling, and potential vision loss.

Treatment for retinal diseases varies depending on the specific condition and its severity. Some treatments include medication, laser therapy, surgery, or a combination of these options. Regular eye exams are essential for early detection and treatment of retinal diseases.

Nerve fibers are specialized structures that constitute the long, slender processes (axons) of neurons (nerve cells). They are responsible for conducting electrical impulses, known as action potentials, away from the cell body and transmitting them to other neurons or effector organs such as muscles and glands. Nerve fibers are often surrounded by supportive cells called glial cells and are grouped together to form nerve bundles or nerves. These fibers can be myelinated (covered with a fatty insulating sheath called myelin) or unmyelinated, which influences the speed of impulse transmission.

Cerebellar ataxia is a type of ataxia, which refers to a group of disorders that cause difficulties with coordination and movement. Cerebellar ataxia specifically involves the cerebellum, which is the part of the brain responsible for maintaining balance, coordinating muscle movements, and regulating speech and eye movements.

The symptoms of cerebellar ataxia may include:

* Unsteady gait or difficulty walking
* Poor coordination of limb movements
* Tremors or shakiness, especially in the hands
* Slurred or irregular speech
* Abnormal eye movements, such as nystagmus (rapid, involuntary movement of the eyes)
* Difficulty with fine motor tasks, such as writing or buttoning a shirt

Cerebellar ataxia can be caused by a variety of underlying conditions, including:

* Genetic disorders, such as spinocerebellar ataxia or Friedreich's ataxia
* Brain injury or trauma
* Stroke or brain hemorrhage
* Infections, such as meningitis or encephalitis
* Exposure to toxins, such as alcohol or certain medications
* Tumors or other growths in the brain

Treatment for cerebellar ataxia depends on the underlying cause. In some cases, there may be no cure, and treatment is focused on managing symptoms and improving quality of life. Physical therapy, occupational therapy, and speech therapy can help improve coordination, balance, and communication skills. Medications may also be used to treat specific symptoms, such as tremors or muscle spasticity. In some cases, surgery may be recommended to remove tumors or repair damage to the brain.

Color vision defects, also known as color blindness, are conditions in which a person has difficulty distinguishing between certain colors. The most common types of color vision defects involve the inability to distinguish between red and green or blue and yellow. These deficiencies result from an alteration or absence of one or more of the three types of cone cells in the retina that are responsible for normal color vision.

In red-green color vision defects, there is a problem with either the red or green cones, or both. This results in difficulty distinguishing between these two colors and their shades. Protanopia is a type of red-green color vision defect where there is an absence of red cone cells, making it difficult to distinguish between red and green as well as between red and black or green and black. Deuteranopia is another type of red-green color vision defect where there is an absence of green cone cells, resulting in similar difficulties distinguishing between red and green, as well as between blue and yellow.

Blue-yellow color vision defects are less common than red-green color vision defects. Tritanopia is a type of blue-yellow color vision defect where there is an absence of blue cone cells, making it difficult to distinguish between blue and yellow, as well as between blue and purple or yellow and pink.

Color vision defects are usually inherited and present from birth, but they can also result from eye diseases, chemical exposure, aging, or medication side effects. They affect both men and women, although red-green color vision defects are more common in men than in women. People with color vision defects may have difficulty with tasks that require color discrimination, such as matching clothes, selecting ripe fruit, reading colored maps, or identifying warning signals. However, most people with mild to moderate color vision defects can adapt and function well in daily life.

An Optic Nerve Glioma is a type of brain tumor that arises from the glial cells (supportive tissue) within the optic nerve. It is most commonly seen in children, particularly those with neurofibromatosis type 1 (NF1). These tumors are typically slow-growing and may not cause any symptoms, especially if they are small. However, as they grow larger, they can put pressure on the optic nerve, leading to vision loss or other visual disturbances. In some cases, these tumors can also affect nearby structures in the brain, causing additional neurological symptoms. Treatment options may include observation, chemotherapy, radiation therapy, or surgery, depending on the size and location of the tumor, as well as the patient's age and overall health.

Evoked potentials, visual, also known as visually evoked potentials (VEPs), are electrical responses recorded from the brain following the presentation of a visual stimulus. These responses are typically measured using electroencephalography (EEG) and can provide information about the functioning of the visual pathways in the brain.

There are several types of VEPs, including pattern-reversal VEPs and flash VEPs. Pattern-reversal VEPs are elicited by presenting alternating checkerboard patterns, while flash VEPs are elicited by flashing a light. The responses are typically analyzed in terms of their latency (the time it takes for the response to occur) and amplitude (the size of the response).

VEPs are often used in clinical settings to help diagnose and monitor conditions that affect the visual system, such as multiple sclerosis, optic neuritis, and brainstem tumors. They can also be used in research to study the neural mechanisms underlying visual perception.

Retinitis pigmentosa (RP) is a group of rare, genetic disorders that involve a breakdown and loss of cells in the retina - a light-sensitive tissue located at the back of the eye. The retina converts light into electrical signals which are then sent to the brain and interpreted as visual images.

In RP, the cells that detect light (rods and cones) degenerate more slowly than other cells in the retina, leading to a progressive loss of vision. Symptoms typically begin in childhood with night blindness (difficulty seeing in low light), followed by a gradual narrowing of the visual field (tunnel vision). Over time, this can lead to significant vision loss and even blindness.

The condition is usually inherited and there are several different genes that have been associated with RP. The diagnosis is typically made based on a combination of genetic testing, family history, and clinical examination. Currently, there is no cure for RP, but researchers are actively working to develop new treatments that may help slow or stop the progression of the disease.

Medical Definition:

Magnetic Resonance Imaging (MRI) is a non-invasive diagnostic imaging technique that uses a strong magnetic field and radio waves to create detailed cross-sectional or three-dimensional images of the internal structures of the body. The patient lies within a large, cylindrical magnet, and the scanner detects changes in the direction of the magnetic field caused by protons in the body. These changes are then converted into detailed images that help medical professionals to diagnose and monitor various medical conditions, such as tumors, injuries, or diseases affecting the brain, spinal cord, heart, blood vessels, joints, and other internal organs. MRI does not use radiation like computed tomography (CT) scans.

Retinal dystrophies are a group of genetic eye disorders that primarily affect the retina, a light-sensitive layer at the back of the eye. These conditions are characterized by progressive degeneration and death of photoreceptor cells (rods and cones) in the retina, leading to vision loss.

The term "dystrophy" refers to a condition that results from the abnormal or defective development and function of tissues or organs. In the case of retinal dystrophies, the photoreceptor cells do not develop or function properly, resulting in visual impairment.

Retinal dystrophies can present at any age, from infancy to adulthood, and can have varying degrees of severity. Some common symptoms include night blindness, decreased visual acuity, loss of peripheral vision, light sensitivity, and color vision abnormalities.

Examples of retinal dystrophies include retinitis pigmentosa, Stargardt disease, Usher syndrome, and Leber congenital amaurosis, among others. These conditions are typically inherited and can be caused by mutations in various genes that play a role in the development and function of the retina.

There is currently no cure for retinal dystrophies, but research is ongoing to develop treatments that may slow or halt the progression of these conditions, such as gene therapy and stem cell transplantation.

Optical coherence tomography (OCT) is a non-invasive imaging technique that uses low-coherence light to capture high-resolution cross-sectional images of biological tissues, particularly the retina and other ocular structures. OCT works by measuring the echo time delay of light scattered back from different depths within the tissue, creating a detailed map of the tissue's structure. This technique is widely used in ophthalmology to diagnose and monitor various eye conditions such as macular degeneration, diabetic retinopathy, and glaucoma.

A phenotype is the physical or biochemical expression of an organism's genes, or the observable traits and characteristics resulting from the interaction of its genetic constitution (genotype) with environmental factors. These characteristics can include appearance, development, behavior, and resistance to disease, among others. Phenotypes can vary widely, even among individuals with identical genotypes, due to differences in environmental influences, gene expression, and genetic interactions.

Optic nerve diseases refer to a group of conditions that affect the optic nerve, which transmits visual information from the eye to the brain. These diseases can cause various symptoms such as vision loss, decreased visual acuity, changes in color vision, and visual field defects. Examples of optic nerve diseases include optic neuritis (inflammation of the optic nerve), glaucoma (damage to the optic nerve due to high eye pressure), optic nerve damage from trauma or injury, ischemic optic neuropathy (lack of blood flow to the optic nerve), and optic nerve tumors. Treatment for optic nerve diseases varies depending on the specific condition and may include medications, surgery, or lifestyle changes.

Genetic linkage is the phenomenon where two or more genetic loci (locations on a chromosome) tend to be inherited together because they are close to each other on the same chromosome. This occurs during the process of sexual reproduction, where homologous chromosomes pair up and exchange genetic material through a process called crossing over.

The closer two loci are to each other on a chromosome, the lower the probability that they will be separated by a crossover event. As a result, they are more likely to be inherited together and are said to be linked. The degree of linkage between two loci can be measured by their recombination frequency, which is the percentage of meiotic events in which a crossover occurs between them.

Linkage analysis is an important tool in genetic research, as it allows researchers to identify and map genes that are associated with specific traits or diseases. By analyzing patterns of linkage between markers (identifiable DNA sequences) and phenotypes (observable traits), researchers can infer the location of genes that contribute to those traits or diseases on chromosomes.

Animal disease models are specialized animals, typically rodents such as mice or rats, that have been genetically engineered or exposed to certain conditions to develop symptoms and physiological changes similar to those seen in human diseases. These models are used in medical research to study the pathophysiology of diseases, identify potential therapeutic targets, test drug efficacy and safety, and understand disease mechanisms.

The genetic modifications can include knockout or knock-in mutations, transgenic expression of specific genes, or RNA interference techniques. The animals may also be exposed to environmental factors such as chemicals, radiation, or infectious agents to induce the disease state.

Examples of animal disease models include:

1. Mouse models of cancer: Genetically engineered mice that develop various types of tumors, allowing researchers to study cancer initiation, progression, and metastasis.
2. Alzheimer's disease models: Transgenic mice expressing mutant human genes associated with Alzheimer's disease, which exhibit amyloid plaque formation and cognitive decline.
3. Diabetes models: Obese and diabetic mouse strains like the NOD (non-obese diabetic) or db/db mice, used to study the development of type 1 and type 2 diabetes, respectively.
4. Cardiovascular disease models: Atherosclerosis-prone mice, such as ApoE-deficient or LDLR-deficient mice, that develop plaque buildup in their arteries when fed a high-fat diet.
5. Inflammatory bowel disease models: Mice with genetic mutations affecting intestinal barrier function and immune response, such as IL-10 knockout or SAMP1/YitFc mice, which develop colitis.

Animal disease models are essential tools in preclinical research, but it is important to recognize their limitations. Differences between species can affect the translatability of results from animal studies to human patients. Therefore, researchers must carefully consider the choice of model and interpret findings cautiously when applying them to human diseases.

Olivopontocerebellar atrophies (OPCA) are a group of rare, progressive neurodegenerative disorders that primarily affect the cerebellum, olive (inferior olivary nucleus), and pons in the brainstem. The condition is characterized by degeneration and atrophy of these specific areas, leading to various neurological symptoms.

The term "olivopontocerebellar atrophies" encompasses several subtypes, including:

1. Hereditary spastic paraplegia with cerebellar ataxia (SPG/ATA) - Autosomal dominant or recessive inheritance pattern.
2. Hereditary dentatorubral-pallidoluysian atrophy (DRPLA) - Autosomal dominant inheritance pattern.
3. Idiopathic OPCA - No known genetic cause, possibly related to environmental factors or spontaneous mutations.

Symptoms of olivopontocerebellar atrophies may include:

* Progressive cerebellar ataxia (gait and limb incoordination)
* Dysarthria (slurred speech)
* Oculomotor abnormalities (nystagmus, gaze palsy)
* Spasticity (stiffness and rigidity of muscles)
* Dysphagia (difficulty swallowing)
* Tremors or dystonia (involuntary muscle contractions)

Diagnosis typically involves a combination of clinical examination, neuroimaging studies (MRI), genetic testing, and exclusion of other possible causes. Currently, there is no cure for olivopontocerebellar atrophies, but supportive care can help manage symptoms and improve quality of life.

Genetic heterogeneity is a phenomenon in genetics where different genetic variations or mutations in various genes can result in the same or similar phenotypic characteristics, disorders, or diseases. This means that multiple genetic alterations can lead to the same clinical presentation, making it challenging to identify the specific genetic cause based on the observed symptoms alone.

There are two main types of genetic heterogeneity:

1. Allelic heterogeneity: Different mutations in the same gene can cause the same or similar disorders. For example, various mutations in the CFTR gene can lead to cystic fibrosis, a genetic disorder affecting the respiratory and digestive systems.
2. Locus heterogeneity: Mutations in different genes can result in the same or similar disorders. For instance, mutations in several genes, such as BRCA1, BRCA2, and PALB2, are associated with an increased risk of developing breast cancer.

Genetic heterogeneity is essential to consider when diagnosing genetic conditions, evaluating recurrence risks, and providing genetic counseling. It highlights the importance of comprehensive genetic testing and interpretation for accurate diagnosis and appropriate management of genetic disorders.

A homozygote is an individual who has inherited the same allele (version of a gene) from both parents and therefore possesses two identical copies of that allele at a specific genetic locus. This can result in either having two dominant alleles (homozygous dominant) or two recessive alleles (homozygous recessive). In contrast, a heterozygote has inherited different alleles from each parent for a particular gene.

The term "homozygote" is used in genetics to describe the genetic makeup of an individual at a specific locus on their chromosomes. Homozygosity can play a significant role in determining an individual's phenotype (observable traits), as having two identical alleles can strengthen the expression of certain characteristics compared to having just one dominant and one recessive allele.

Photoreceptor cells in vertebrates are specialized types of neurons located in the retina of the eye that are responsible for converting light stimuli into electrical signals. These cells are primarily responsible for the initial process of vision and have two main types: rods and cones.

Rods are more numerous and are responsible for low-light vision or scotopic vision, enabling us to see in dimly lit conditions. They do not contribute to color vision but provide information about the shape and movement of objects.

Cones, on the other hand, are less numerous and are responsible for color vision and high-acuity vision or photopic vision. There are three types of cones, each sensitive to different wavelengths of light: short (S), medium (M), and long (L) wavelengths, which correspond to blue, green, and red, respectively. The combination of signals from these three types of cones allows us to perceive a wide range of colors.

Both rods and cones contain photopigments that consist of a protein called opsin and a light-sensitive chromophore called retinal. When light hits the photopigment, it triggers a series of chemical reactions that ultimately lead to the generation of an electrical signal that is transmitted to the brain via the optic nerve. This process enables us to see and perceive our visual world.

Leigh Disease, also known as Subacute Necrotizing Encephalomyelopathy (SNE), is a rare inherited neurometabolic disorder that affects the central nervous system. It is characterized by progressive degeneration of the brain and spinal cord. The condition typically appears in infancy or early childhood, although it can develop in adolescence or adulthood.

Leigh Disease is caused by mutations in mitochondrial DNA or nuclear genes that disrupt the function of the oxidative phosphorylation system, a part of the cellular energy production process. This results in decreased ATP (adenosine triphosphate) production and an accumulation of lactic acid in the body.

The symptoms of Leigh Disease can vary widely but often include vomiting, seizures, developmental delays, muscle weakness, loss of muscle tone, and difficulty swallowing and breathing. The condition can also cause lesions to form on the brainstem and basal ganglia, which can lead to further neurological problems.

There is no cure for Leigh Disease, and treatment is focused on managing symptoms and supporting affected individuals as they cope with the progression of the disease.

Molecular sequence data refers to the specific arrangement of molecules, most commonly nucleotides in DNA or RNA, or amino acids in proteins, that make up a biological macromolecule. This data is generated through laboratory techniques such as sequencing, and provides information about the exact order of the constituent molecules. This data is crucial in various fields of biology, including genetics, evolution, and molecular biology, allowing for comparisons between different organisms, identification of genetic variations, and studies of gene function and regulation.

Membrane proteins are a type of protein that are embedded in the lipid bilayer of biological membranes, such as the plasma membrane of cells or the inner membrane of mitochondria. These proteins play crucial roles in various cellular processes, including:

1. Cell-cell recognition and signaling
2. Transport of molecules across the membrane (selective permeability)
3. Enzymatic reactions at the membrane surface
4. Energy transduction and conversion
5. Mechanosensation and signal transduction

Membrane proteins can be classified into two main categories: integral membrane proteins, which are permanently associated with the lipid bilayer, and peripheral membrane proteins, which are temporarily or loosely attached to the membrane surface. Integral membrane proteins can further be divided into three subcategories based on their topology:

1. Transmembrane proteins, which span the entire width of the lipid bilayer with one or more alpha-helices or beta-barrels.
2. Lipid-anchored proteins, which are covalently attached to lipids in the membrane via a glycosylphosphatidylinositol (GPI) anchor or other lipid modifications.
3. Monotopic proteins, which are partially embedded in the membrane and have one or more domains exposed to either side of the bilayer.

Membrane proteins are essential for maintaining cellular homeostasis and are targets for various therapeutic interventions, including drug development and gene therapy. However, their structural complexity and hydrophobicity make them challenging to study using traditional biochemical methods, requiring specialized techniques such as X-ray crystallography, nuclear magnetic resonance (NMR) spectroscopy, and single-particle cryo-electron microscopy (cryo-EM).

A visual field test is a method used to measure an individual's entire scope of vision, which includes what can be seen straight ahead and in peripheral (or side) vision. During the test, the person being tested is asked to focus on a central point while gradually identifying the appearance of objects moving into their peripheral vision. The visual field test helps detect blind spots (scotomas) or gaps in the visual field, which can be caused by various conditions such as glaucoma, brain injury, optic nerve damage, or retinal disorders. It's an essential tool for diagnosing and monitoring eye-related diseases and conditions.

Gyrate atrophy is a rare inherited eye disorder that is characterized by progressive degeneration of the retina, which is the light-sensitive tissue at the back of the eye. It is caused by a deficiency in an enzyme called ornithine aminotransferase (OAT), which is necessary for the normal metabolism of an amino acid called ornithine.

The accumulation of ornithine in the retinal cells leads to their degeneration and the formation of well-demarcated, circular areas of atrophy (gyrates) in the retina. This can result in decreased vision, night blindness, and a progressive loss of visual field, which can ultimately lead to legal or complete blindness.

Gyrate atrophy is typically inherited as an autosomal recessive trait, meaning that an individual must inherit two copies of the mutated gene (one from each parent) in order to develop the condition. The disorder usually becomes apparent in childhood or adolescence and can progress slowly over several decades. There is currently no cure for gyrate atrophy, but dietary restrictions and supplements may help slow its progression.

Deafness is a hearing loss that is so severe that it results in significant difficulty in understanding or comprehending speech, even when using hearing aids. It can be congenital (present at birth) or acquired later in life due to various causes such as disease, injury, infection, exposure to loud noises, or aging. Deafness can range from mild to profound and may affect one ear (unilateral) or both ears (bilateral). In some cases, deafness may be accompanied by tinnitus, which is the perception of ringing or other sounds in the ears.

Deaf individuals often use American Sign Language (ASL) or other forms of sign language to communicate. Some people with less severe hearing loss may benefit from hearing aids, cochlear implants, or other assistive listening devices. Deafness can have significant social, educational, and vocational implications, and early intervention and appropriate support services are critical for optimal development and outcomes.

Penetrance, in medical genetics, refers to the proportion of individuals with a particular genetic variant or mutation who exhibit clinical features or symptoms of a resulting disease. It is often expressed as a percentage, with complete penetrance indicating that all individuals with the genetic change will develop the disease, and reduced or incomplete penetrance suggesting that not all individuals with the genetic change will necessarily develop the disease, even if they express some of its characteristics.

Penetrance can vary depending on various factors such as age, sex, environmental influences, and interactions with other genes. Incomplete penetrance is common in many genetic disorders, making it challenging to predict who will develop symptoms based solely on their genotype.

Hereditary eye diseases refer to conditions that affect the eyes and are passed down from parents to their offspring through genetics. These diseases are caused by mutations or changes in an individual's DNA that are inherited from their parents. The mutations can occur in any of the genes associated with eye development, function, or health.

There are many different types of hereditary eye diseases, some of which include:

1. Retinitis Pigmentosa - a group of rare, genetic disorders that involve a breakdown and loss of cells in the retina.
2. Macular Degeneration - a progressive disease that damages the central portion of the retina, impairing vision.
3. Glaucoma - a group of eye conditions that damage the optic nerve, often caused by an increase in pressure inside the eye.
4. Cataracts - clouding of the lens inside the eye, which can lead to blurry vision and blindness.
5. Keratoconus - a progressive eye disease that causes the cornea to thin and bulge outward into a cone shape.
6. Color Blindness - a condition where an individual has difficulty distinguishing between certain colors.
7. Optic Neuropathy - damage to the optic nerve, which can result in vision loss.

The symptoms and severity of hereditary eye diseases can vary widely depending on the specific condition and the individual's genetic makeup. Some conditions may be present at birth or develop in early childhood, while others may not appear until later in life. Treatment options for these conditions may include medication, surgery, or lifestyle changes, and are often most effective when started early.

Dominant genes refer to the alleles (versions of a gene) that are fully expressed in an individual's phenotype, even if only one copy of the gene is present. In dominant inheritance patterns, an individual needs only to receive one dominant allele from either parent to express the associated trait. This is in contrast to recessive genes, where both copies of the gene must be the recessive allele for the trait to be expressed. Dominant genes are represented by uppercase letters (e.g., 'A') and recessive genes by lowercase letters (e.g., 'a'). If an individual inherits one dominant allele (A) from either parent, they will express the dominant trait (A).

Sensorineural hearing loss (SNHL) is a type of hearing impairment that occurs due to damage to the inner ear (cochlea) or to the nerve pathways from the inner ear to the brain. It can be caused by various factors such as aging, exposure to loud noises, genetics, certain medical conditions (like diabetes and heart disease), and ototoxic medications.

SNHL affects the ability of the hair cells in the cochlea to convert sound waves into electrical signals that are sent to the brain via the auditory nerve. As a result, sounds may be perceived as muffled, faint, or distorted, making it difficult to understand speech, especially in noisy environments.

SNHL is typically permanent and cannot be corrected with medication or surgery, but hearing aids or cochlear implants can help improve communication and quality of life for those affected.

Human chromosome pair 3 consists of two rod-shaped structures present in the nucleus of each cell in the human body. Each member of the pair is a single chromosome, and together they contain the genetic material that is inherited from both parents. Chromosomes are made up of DNA, which contains the instructions for the development and function of all living organisms.

Human chromosomes are numbered from 1 to 22, with an additional two sex chromosomes (X and Y) that determine biological sex. Chromosome pair 3 is one of the autosomal pairs, meaning it contains genes that are not related to sex determination. Each member of chromosome pair 3 is identical in size and shape and contains a single long DNA molecule that is coiled tightly around histone proteins to form a compact structure.

Chromosome pair 3 is associated with several genetic disorders, including Waardenburg syndrome, which affects pigmentation and hearing; Marfan syndrome, which affects the connective tissue; and some forms of retinoblastoma, a rare eye cancer that typically affects young children.

Night vision refers to the ability to see in low light conditions, typically during night time. In a medical context, it often relates to the functionality of the eye and visual system. There are two types of night vision:

1. Scotopic vision: This is the primary type of night vision, enabled by the rod cells in our retina which are highly sensitive to light but lack color vision. During twilight or night conditions, when light levels are low, the rods take over from the cone cells (which are responsible for color and daytime vision) and provide us with limited vision, typically in shades of gray.

2. Mesopic vision: This is a state between photopic (daytime) and scotopic (night-time) vision, where both rod and cone cells contribute to vision. It allows for better color discrimination and visual acuity compared to scotopic vision alone.

In some cases, night vision can be impaired due to eye conditions such as cataracts, glaucoma, or retinal disorders. There are also medical devices called night vision goggles that amplify available light to enhance a person's ability to see in low-light environments.

The Founder Effect is a concept in population genetics that refers to the loss of genetic variation that occurs when a new colony is established by a small number of individuals from a larger population. This decrease in genetic diversity can lead to an increase in homozygosity, which can in turn result in a higher frequency of certain genetic disorders or traits within the founding population and its descendants. The Founder Effect is named after the "founding" members of the new colony who carry and pass on their particular set of genes to the next generations. It is one of the mechanisms that can lead to the formation of distinct populations or even new species over time.

A haplotype is a group of genes or DNA sequences that are inherited together from a single parent. It refers to a combination of alleles (variant forms of a gene) that are located on the same chromosome and are usually transmitted as a unit. Haplotypes can be useful in tracing genetic ancestry, understanding the genetic basis of diseases, and developing personalized medical treatments.

In population genetics, haplotypes are often used to study patterns of genetic variation within and between populations. By comparing haplotype frequencies across populations, researchers can infer historical events such as migrations, population expansions, and bottlenecks. Additionally, haplotypes can provide information about the evolutionary history of genes and genomic regions.

In clinical genetics, haplotypes can be used to identify genetic risk factors for diseases or to predict an individual's response to certain medications. For example, specific haplotypes in the HLA gene region have been associated with increased susceptibility to certain autoimmune diseases, while other haplotypes in the CYP450 gene family can affect how individuals metabolize drugs.

Overall, haplotypes provide a powerful tool for understanding the genetic basis of complex traits and diseases, as well as for developing personalized medical treatments based on an individual's genetic makeup.

Neurodegenerative diseases are a group of disorders characterized by progressive and persistent loss of neuronal structure and function, often leading to cognitive decline, functional impairment, and ultimately death. These conditions are associated with the accumulation of abnormal protein aggregates, mitochondrial dysfunction, oxidative stress, chronic inflammation, and genetic mutations in the brain. Examples of neurodegenerative diseases include Alzheimer's disease, Parkinson's disease, Huntington's disease, Amyotrophic Lateral Sclerosis (ALS), and Spinal Muscular Atrophy (SMA). The underlying causes and mechanisms of these diseases are not fully understood, and there is currently no cure for most neurodegenerative disorders. Treatment typically focuses on managing symptoms and slowing disease progression.

Intellectual disability (ID) is a term used when there are significant limitations in both intellectual functioning and adaptive behavior, which covers many everyday social and practical skills. This disability originates before the age of 18.

Intellectual functioning, also known as intelligence, refers to general mental capacity, such as learning, reasoning, problem-solving, and other cognitive skills. Adaptive behavior includes skills needed for day-to-day life, such as communication, self-care, social skills, safety judgement, and basic academic skills.

Intellectual disability is characterized by below-average intelligence or mental ability and a lack of skills necessary for day-to-day living. It can be mild, moderate, severe, or profound, depending on the degree of limitation in intellectual functioning and adaptive behavior.

It's important to note that people with intellectual disabilities have unique strengths and limitations, just like everyone else. With appropriate support and education, they can lead fulfilling lives and contribute to their communities in many ways.

Geographic atrophy is a medical term used to describe a specific pattern of degeneration of the retinal pigment epithelium (RPE) and the underlying choroidal tissue in the eye. This condition is often associated with age-related macular degeneration (AMD), which is a leading cause of vision loss in older adults.

In geographic atrophy, there are well-defined areas of RPE and choroidal atrophy that appear as pale, irregularly shaped patches in the central part of the retina known as the macula. These patches can grow larger over time and may lead to progressive vision loss. The exact cause of geographic atrophy is not fully understood, but it is thought to be related to oxidative stress, inflammation, and other age-related changes in the eye.

Currently, there are no effective treatments for geographic atrophy, although research is ongoing to find new ways to slow or halt its progression. Regular eye exams and monitoring by an ophthalmologist are important for people with AMD or geographic atrophy to help detect any changes in their vision and manage their condition effectively.

'Abnormalities, Multiple' is a broad term that refers to the presence of two or more structural or functional anomalies in an individual. These abnormalities can be present at birth (congenital) or can develop later in life (acquired). They can affect various organs and systems of the body and can vary greatly in severity and impact on a person's health and well-being.

Multiple abnormalities can occur due to genetic factors, environmental influences, or a combination of both. Chromosomal abnormalities, gene mutations, exposure to teratogens (substances that cause birth defects), and maternal infections during pregnancy are some of the common causes of multiple congenital abnormalities.

Examples of multiple congenital abnormalities include Down syndrome, Turner syndrome, and VATER/VACTERL association. Acquired multiple abnormalities can result from conditions such as trauma, infection, degenerative diseases, or cancer.

The medical evaluation and management of individuals with multiple abnormalities depend on the specific abnormalities present and their impact on the individual's health and functioning. A multidisciplinary team of healthcare professionals is often involved in the care of these individuals to address their complex needs.

A base sequence in the context of molecular biology refers to the specific order of nucleotides in a DNA or RNA molecule. In DNA, these nucleotides are adenine (A), guanine (G), cytosine (C), and thymine (T). In RNA, uracil (U) takes the place of thymine. The base sequence contains genetic information that is transcribed into RNA and ultimately translated into proteins. It is the exact order of these bases that determines the genetic code and thus the function of the DNA or RNA molecule.

Genetic testing is a type of medical test that identifies changes in chromosomes, genes, or proteins. The results of a genetic test can confirm or rule out a suspected genetic condition or help determine a person's chance of developing or passing on a genetic disorder. Genetic tests are performed on a sample of blood, hair, skin, amniotic fluid (the fluid that surrounds a fetus during pregnancy), or other tissue. For example, a physician may recommend genetic testing to help diagnose a genetic condition, confirm the presence of a gene mutation known to increase the risk of developing certain cancers, or determine the chance for a couple to have a child with a genetic disorder.

There are several types of genetic tests, including:

* Diagnostic testing: This type of test is used to identify or confirm a suspected genetic condition in an individual. It may be performed before birth (prenatal testing) or at any time during a person's life.
* Predictive testing: This type of test is used to determine the likelihood that a person will develop a genetic disorder. It is typically offered to individuals who have a family history of a genetic condition but do not show any symptoms themselves.
* Carrier testing: This type of test is used to determine whether a person carries a gene mutation for a genetic disorder. It is often offered to couples who are planning to have children and have a family history of a genetic condition or belong to a population that has an increased risk of certain genetic disorders.
* Preimplantation genetic testing: This type of test is used in conjunction with in vitro fertilization (IVF) to identify genetic changes in embryos before they are implanted in the uterus. It can help couples who have a family history of a genetic disorder or who are at risk of having a child with a genetic condition to conceive a child who is free of the genetic change in question.
* Pharmacogenetic testing: This type of test is used to determine how an individual's genes may affect their response to certain medications. It can help healthcare providers choose the most effective medication and dosage for a patient, reducing the risk of adverse drug reactions.

It is important to note that genetic testing should be performed under the guidance of a qualified healthcare professional who can interpret the results and provide appropriate counseling and support.

Leber's hereditary optic neuropathy Charcot-Marie-Tooth disease Hagemoser; et al. (1989). "Optic atrophy, hearing loss, and ... Optic atrophy occurs in the first year and the following symptoms show up before thirteen years. A possible autosomal recessive ... It is characterized by optic atrophy followed shortly by loss of hearing and peripheral neuropathy. Onset of the disease ... Iwashita, H.; Inoue, N.; Kuroiwa, Y. (1969). "Familial optic and acoustic nerve degeneration with distal amyotrophy". Lancet. ...
List of systemic diseases with ocular manifestations Leber's Hereditary Optic Atrophy Mitochondrial Disorders Optic Atrophy ... OPA3 or C12ORF65 genes which are known causes of pure optic atrophy or optic atrophy complicated by movement disorder. Onset : ... Optic Atrophy Plus Syndrome Ocular: Optic atrophy, nystagmus, scotoma, and bilateral retrobulbar neuritis. Other: Mental ... Behr syndrome is characterized by the association of early-onset optic atrophy with spinocerebellar degeneration resulting in ...
... optic atrophy, hereditary, leber MeSH C18.452.660.520 - Leigh disease MeSH C18.452.660.560 - mitochondrial myopathies MeSH ... optic atrophy, autosomal dominant MeSH C18.452.660.705 - pyruvate carboxylase deficiency disease MeSH C18.452.660.710 - ... hereditary nonpolyposis MeSH C18.452.284.280 - fanconi anemia MeSH C18.452.284.520 - Li-Fraumeni syndrome MeSH C18.452.284.600 ... hereditary MeSH C18.452.648.437.281 - Crigler-Najjar syndrome MeSH C18.452.648.437.528 - gilbert disease MeSH C18.452.648.499 ...
... optic atrophy MeSH C11.640.451.451 - optic atrophies, hereditary MeSH C11.640.451.451.400 - optic atrophy, hereditary, leber ... optic atrophies, hereditary MeSH C11.270.564.400 - optic atrophy, hereditary, leber MeSH C11.270.564.500 - optic atrophy, ... optic disk drusen MeSH C11.640.530 - optic nerve injuries MeSH C11.640.544 - optic nerve neoplasms MeSH C11.640.544.500 - optic ... optic atrophy, autosomal dominant MeSH C11.640.451.451.980 - wolfram syndrome MeSH C11.640.513 - ...
Amaurosis Dominant optic atrophy Glaucoma Ischemic optic neuropathy Optic atrophy Toxic and nutritional optic neuropathy ... Leber's hereditary optic neuropathy at NLM Genetics Home Reference Kerrison JB, Newman NJ (1997). "Clinical spectrum of Leber's ... August 1995). "Leber's "plus": neurological abnormalities in patients with Leber's hereditary optic neuropathy". J. Neurol. ... Leber hereditary optic neuropathy is a condition related to changes in mitochondrial DNA. Although most DNA is packaged in ...
... hereditary angioedema, hypertension, IgA nephropathy, Leber's hereditary optic neuropathy, multiple system atrophy, non- ... In 2004, development of an antisense therapy for spinal muscular atrophy began. Over the following years, an antisense ... Inotersen received FDA approval for the treatment of hereditary transthyretin-mediated amyloidosis in October 2018. The ... an RNAi therapeutic for the treatment of hereditary transthyretin-mediated amyloidosis". Neurodegenerative Disease Management. ...
... gyrate atrophy MeSH C16.320.290.564 - optic atrophies, hereditary MeSH C16.320.290.564.400 - optic atrophy, hereditary, leber ... optic atrophies, hereditary MeSH C16.320.400.630.400 - optic atrophy, hereditary, leber MeSH C16.320.400.630.500 - optic ... optic atrophy, autosomal dominant MeSH C16.320.290.564.980 - Wolfram syndrome MeSH C16.320.290.660 - retinal dysplasia MeSH ... hereditary central nervous system demyelinating diseases MeSH C16.320.400.400 - hereditary motor and sensory neuropathies MeSH ...
Optic nerve damage in most inherited optic neuropathies is permanent and progressive. Leber's hereditary optic neuropathy (LHON ... Optic neuropathy is often called optic atrophy, to describe the loss of some or most of the fibers of the optic nerve. In ... Oostra, R. J; Bolhuis, P. A; Wijburg, F. A; Zorn-Ende, G; Bleeker-Wagemakers, E. M (1994). "Leber's hereditary optic neuropathy ... Dominant optic atrophy is an autosomal dominant disease caused by a defect in the nuclear gene OPA1. A slowly progressive optic ...
... optic atrophies, hereditary MeSH C10.574.500.662.400 - optic atrophy, hereditary, leber MeSH C10.574.500.662.500 - optic ... optic atrophy MeSH C10.292.700.225.500 - optic atrophies, hereditary MeSH C10.292.700.225.500.400 - optic atrophy, hereditary, ... leber MeSH C10.292.700.225.500.500 - optic atrophy, autosomal dominant MeSH C10.292.700.225.500.980 - wolfram syndrome MeSH ... optic nerve injuries MeSH C10.292.700.500 - optic nerve neoplasms MeSH C10.292.700.500.500 - optic nerve glioma MeSH C10.292. ...
Leber's hereditary optic neuropathy and Kjer's optic neuropathy. The diagnosis of toxic or nutritional optic neuropathy is ... Continued damage to the optic nerve results in the development of optic atrophy, classically seen as temporal pallor of the ... Toxic and nutritional optic neuropathy is a group of medical disorders defined by visual impairment due to optic nerve damage ... Tobacco is also a major cause of toxic optic neuropathy. The predominant cause of nutritional optic neuropathy is thought to be ...
Leber's hereditary optic neuropathy (LHON) is the disease in humans that is most frequently associated with homoplasmy. This ... condition is characterized by the atrophy of retinal ganglion cells, which leads to central blindness and eventually total ... Leber's Hereditary Optic Neuropathy Portal: Biology (Articles with short description, Short description matches Wikidata, Use ... Giordano (2015). "Cigarette toxicity triggers Leber's hereditary optic neuropathy by affecting mtDNA copy number, oxidative ...
Mutations in PARL may also be involved in Leber hereditary optic neuropathy by disrupting normal function of the mitochondria, ... Additionally, PARL is involved in apoptosis through its interactions with the mitochondrial GTPase optic atrophy 1 (OPA1) and ...
Luxturna is an approved gene therapy to treat Leber's hereditary optic neuropathy.: 1354 Glybera, a treatment for pancreatitis ... In May, onasemnogene abeparvovec (Zolgensma) was approved by the European Union for the treatment of spinal muscular atrophy in ... Leber's congenital amaurosis is an inherited blinding disease caused by mutations in the RPE65 gene. The results of a small ... In July, Allergan and Editas Medicine announced phase I/II clinical trial of AGN-151587 for the treatment of Leber congenital ...
Oostra, R J; Bolhuis, P A; Wijburg, F A; Zorn-Ende, G; Bleeker-Wagemakers, E M (1994). "Leber's hereditary optic neuropathy: ... Optic atrophy typically develops later and may appear mild. In later stages the optic atrophy can become severe, which ... Cullom, Mary Ellen; Heher, Katrinka L.; Miller, Neil R.; Savino, Peter J.; Johns, Donald R. (1993). "Leber's Hereditary Optic ... For example, 90% of cases of Leber's Hereditary Optic Neuropathy (LHON) are associated with three common mtDNA point mutations ...
Leber hereditary optic neuropathy, and some forms of Parkinson disease. NDUFS3 has also been implicated in breast cancer and ... are causally linked to Leigh syndrome and optic atrophy. Nonetheless, despite its crucial biological role, the human NDUFS3 ...
Leber's hereditary optic neuropathy differentially affects smaller axons in the optic nerve. Transactions of the American ... Inhibition of autophagy curtails visual loss in a model of autosomal dominant optic atrophy. Nature communications, 11(1), 1-12 ... and Atlas of Leber's Hereditary Optic Neuropathy. Sadun is a Gold Fellow of the Association for Research in Vision and ... ISBN 9780323528191 Atlas of Leber's Hereditary Optic Neuropathy (2019) Sadun, A. A., Schaechter, J. D., & Smith, L. E. (1984). ...
... deficiency Lead poisoning Leao Ribeiro Da Silva syndrome Learman syndrome Leber military aneurysm Leber optic atrophy Leber's ... Lymphatic filariasis Lymphatic neoplasm Lymphedema distichiasis Lymphedema hereditary type 1 Lymphedema hereditary type 2 ... isolated Lissencephaly Listeria infection Listeriosis Livedoid dermatitis Liver cirrhosis Liver neoplasms Lobar atrophy of ...
Leber hereditary optic neuropathy, and some forms of Parkinson disease. Pathogenic mutations of FOXRED1 have included c.1054C>T ... Symptoms due to these mutations have included lactic acidosis, hypertrophic cardiomyopathy, and optic atrophy. Clinically, ...
Hereditary causes such as Leber's hereditary optic neuropathy are also part of the differential diagnosis. In 2014, there were ... 2019). "Brain Atrophy in Relapsing Optic Neuritis Is Associated With Crion Phenotype". Frontiers in Neurology. 10: 1157. doi: ... Optic neuritis Optic neuropathy Kidd D, Burton B, Plant GT, Graham EM (February 2003). "Chronic relapsing inflammatory optic ... Chronic relapsing inflammatory optic neuropathy (CRION) is a form of recurrent optic neuritis that is steroid responsive and ...
Bargiela D, Chinnery PF (September 2019). "Mitochondria in neuroinflammation - Multiple sclerosis (MS), leber hereditary optic ... 2019). "Brain Atrophy in Relapsing Optic Neuritis Is Associated With Crion Phenotype". Frontiers in Neurology. 10: 1157. doi: ... neurological abnormalities in patients with Leber's hereditary optic neuropathy". Journal of Neurology, Neurosurgery, and ... These patients have MS-like brain lesions, multifocal spine lesions and retinal and optic nerves atrophy. See Anti-neurofascin ...
Leber hereditary optic neuropathy, and some forms of Parkinson disease. Pathogenic mutations have been linked to changes in a ... cerebral atrophy, and generalized tonic-clonic convulsions as some possible symptoms. HRPAP20 was found to be significantly ...
Optic atrophy (14.1%) Glaucoma (5.9%) Congenital abnormalities (5.1%) Disorders of the visual cortex (4.1%) Cerebrovascular ... known as Leber's congenital amaurosis or LCA. Leber's Congenital Amaurosis damages the light receptors in the retina and ... Among working-age adults who are newly blind in England and Wales the most common causes in 2010 were: Hereditary retinal ... Leber congenital amaurosis can cause total blindness or severe sight loss from birth or early childhood. Retinitis pigmentosa ...
Leber's hereditary optic neuropathy - genetic disorder; loss of central vision,. (H47.3) Optic disc drusen - globules ... Choroidal degeneration Atrophy Sclerosis Excludes: angioid streaks (H35.3) (H31.2) Hereditary choroidal dystrophy Choroideremia ... progressively calcify in the optic disc, compressing the vascularization and optic nerve fibers (H49-H50) Strabismus (Crossed ... Dysthyroid exophthalmos it is shown that if your eye comes out that it will shrink because the optic fluids drain out (H10.0) ...
... and Leber's hereditary optic neuropathy. It was first characterized under this name in 1984. A feature of these diseases is ... MERRF patients may also have hearing loss, visual disturbance secondary to optic atrophy, and short stature. The characteristic ...
... to examine the safety and efficacy of mitochondrial gene therapy in Leber's hereditary optic neuropathy. About 1 in 4,000 ... Cerebellar atrophy or hypoplasia has sometimes been reported to be associated. Mitochondrial disorders may be caused by ... be due to mitochondrial disease Diabetes mellitus and deafness can be found together for other reasons Leber's hereditary optic ... beginning in young adulthood eye disorder characterized by progressive loss of central vision due to degeneration of the optic ...
August 1995). "Leber's "plus": neurological abnormalities in patients with Leber's hereditary optic neuropathy". J. Neurol. ... NEDA-4 means NEDA-3 plus that brain atrophy has not increased. Some authors speak about a NEDA-3+ which is a NEDA-3 plus no ... leber hereditary optic neuropathy (LHON) and LHON-MS". Neuroscience Letters. 710: 132932. doi:10.1016/j.neulet.2017.06.051. ... In the days in which NMO was considered a kind of MS (optic-spinal MS), the four clinical types model on widespread usage, and ...
... and related hereditary degenerations Retinitis punctata albescens Leber's congenital amaurosis Choroideremia Gyrate atrophy of ... He thought the responses he recorded were from the optic nerve instead of the retina. The first human ERG was recorded in 1877 ...
An example of this type of disorder is Leber's hereditary optic neuropathy.[citation needed] It is important to stress that the ... spinal muscular atrophy, and Roberts syndrome. Certain other phenotypes, such as wet versus dry earwax, are also determined in ... but birth defects can also be developmental rather than hereditary. The opposite of a hereditary disease is an acquired disease ... hereditary nonpolyposis colorectal cancer, hereditary multiple exostoses (a highly penetrant autosomal dominant disorder), ...
CYP2C Optic atrophy 1; 165500; OPA1 Optic atrophy and cataract; 165300; OPA3 Optic atrophy and deafness; 125250; OPA1 Optic ... hereditary, type III; 610618; F12 Angioedema, hereditary, types I and II; 106100; C1NH Angiopathy, hereditary, with nephropathy ... GUCY2D Leber congenital amaurosis 10; 611755; CEP290 Leber congenital amaurosis 12; 610612; RD3 Leber congenital amaurosis 13; ... UBE1 Spinal muscular atrophy-1; 253300; SMN1 Spinal muscular atrophy-2; 253550; SMN1 Spinal muscular atrophy-3; 253400; SMN1 ...
Several hereditary studies have been performed to determine the varying prevalence rates in Maine (USA), Birmingham (England), ... Clinical trials investigating optic prosthetic devices, gene therapy mechanisms, and retinal sheet transplantations are active ... Currently there is only one FDA-approved gene therapy that is commercially available to RP patients with Leber congenital ... Management Department at Columbia Business School Cone dystrophy List of eye diseases and disorders Progressive retinal atrophy ...
Leber Optic Atrophy) Pipeline Report is a comprehensive report on the pre-clinical and clinical stage pipeline candidates ... 2.1 Lebers Hereditary Optic Neuropathy (Leber Optic Atrophy) Drugs by Phase of Development. 2.2 Lebers Hereditary Optic ... 2.3 Lebers Hereditary Optic Neuropathy (Leber Optic Atrophy) Drugs by Route of Administration. 2.4 Lebers Hereditary Optic ... 2.1 Lebers Hereditary Optic Neuropathy (Leber Optic Atrophy) Drugs by Phase of Development. 2.2 Lebers Hereditary Optic ...
Leber hereditary optic neuropathy (LHON) is an inherited form of vision loss. Explore symptoms, inheritance, genetics of this ... Hereditary optic neuroretinopathy. *Leber hereditary optic atrophy. *Leber optic atrophy. *Lebers hereditary optic neuropathy ... medlineplus.gov/genetics/condition/leber-hereditary-optic-neuropathy/ Leber hereditary optic neuropathy. ... Leber hereditary optic neuropathy. J Med Genet. 2002 Mar;39(3):162-9. doi: 10.1136/jmg.39.3.162. Citation on PubMed or Free ...
... J Med Genet. 2004 Apr;41(4):e41. ...
Lebers hereditary optic neuropathy (LHON), the most frequent mitochondrial disorder, is mostly due to three mitochondrial DNA ... Optic Atrophy, Hereditary, Leber / genetics* * Optic Atrophy, Hereditary, Leber / metabolism * Optic Atrophy, Hereditary, Leber ... Lebers hereditary optic neuropathy (LHON), the most frequent mitochondrial disorder, is mostly due to three mitochondrial DNA ...
Lebers hereditary optic atrophy (LHON), an eye disease;. *myoclonic epilepsy with ragged red fibers (MERRF); and ...
Lebers hereditary optic neuropathy (LHON) or Autosomal dominant optic atrophy (ADOA). *Leigh syndrome ...
Optic atrophy. Leber hereditary optic atrophy (any of the several mitochondrial DNA mutations) ... optic nerve swelling and atrophy, ocular hypertension, and glaucoma. Corneal opacification of varying severity is frequently ... Optic atrophy. Leber hereditary optic atrophy (any of the several mitochondrial DNA mutations) ...
Lebers hereditary optic neuropathy Charcot-Marie-Tooth disease Hagemoser; et al. (1989). "Optic atrophy, hearing loss, and ... Optic atrophy occurs in the first year and the following symptoms show up before thirteen years. A possible autosomal recessive ... It is characterized by optic atrophy followed shortly by loss of hearing and peripheral neuropathy. Onset of the disease ... Iwashita, H.; Inoue, N.; Kuroiwa, Y. (1969). "Familial optic and acoustic nerve degeneration with distal amyotrophy". Lancet. ...
... such as Leber hereditary optic neuropathy (LHON), that result from inherited mutations in the mitochondrial DNA; and diseases ... Other articles where Lebers disease is discussed: human genetic disease: Diseases associated with single-gene non-Mendelian ... optic atrophy. *. In optic atrophy. …hereditary defect, such as in Leber hereditary optic neuropathy (LHON), which ... of neurodegenerative disorders, such as Leber hereditary optic neuropathy (LHON), that result from inherited mutations in the ...
Patients with early Lebers disease (hereditary optic nerve atrophy) who were treated with cyanocobalamin suffered severe and ...
Hereditary Optic Neuropathies - Etiology, pathophysiology, symptoms, signs, diagnosis & prognosis from the MSD Manuals - ... Hereditary optic neuropathies include dominant optic atrophy and Leber hereditary optic neuropathy, which are both ... Diagnosis of dominant optic atrophy and Leber hereditary optic atrophy is mainly clinical. Molecular genetic testing is ... Symptoms and Signs of Hereditary Optic Neuropathies Dominant optic atrophy Most patients with dominant optic atrophy have no ...
Patients with early Lebers disease (hereditary optic nerve atrophy) who were treated with cyanocobalamin suffered severe and ...
lebers hereditary optic atrophy. November 13, 2018 * beanbag chair. November 12, 2018 ...
Learn how to identify and manage optic neuritis. ... Lebers hereditary optic neuropathy. *Progressive vision loss ... Kjer type autosomal dominant optic atrophy. *Usually presents in childhood, bilateral and symmetric optic atrophy. ... Although optic neuritis is more common earlier in the course of MS, patients with MS can have optic neuritis at any point in ... Optic neuritis (ON) is a common manifestation of multiple sclerosis (MS), and refers to inflammation of the optic nerve. It can ...
... spinal muscular atrophy) and blindness (Leber Hereditary Optic Neuropathy, a form of retinitis pigmentosa)," Tuszynski said. ...
Lebers Hereditary Optic Atrophy Medicine & Life Sciences 88% * Visual Acuity Medicine & Life Sciences 44% ... N2 - Background:Leber hereditary optic neuropathy (LHON) leads to bilateral central vision loss. In a clinical trial setting, ... AB - Background:Leber hereditary optic neuropathy (LHON) leads to bilateral central vision loss. In a clinical trial setting, ... Background:Leber hereditary optic neuropathy (LHON) leads to bilateral central vision loss. In a clinical trial setting, ...
... and optic nerve (7.1%). A high proportion of parents were in a consanguineous marriage (49.2%). The pattern of blindness in ... The major causes of abnormality were hereditary factors (42.7%), prenatal/ neonatal (18.5%) and unknown etiology (35.5%). The ... Optic atrophy accounted for 7.1%, and retinal detachment for 4.7%. ROP was seen in only 0.9% of children. The major causes of ... Hereditary disease as a cause of childhood blindness: regional variation. Ophthalmic genetics, 1995, 16:1-10. ...
Lebers hereditary optic atrophy.. *inflammation of the stomach called atrophic gastritis.. *past history of complete removal ...
Lebers Hereditary Optic Atrophy 94% * peripheral nervous system diseases 90% * Induced Pluripotent Stem Cells 72% ... Induced pluripotent stem cell-based leber hereditary optic neuropathy model. Wu, Y. R., Yang, T. C., Yarmishyn, A. A., Chen, S ...
Lebers Hereditary Optic Atrophy Medicine & Life Sciences 88% * Bevacizumab Medicine & Life Sciences 67% ... Clinical outcomes of treatment with idebenone in Lebers hereditary optic neuropathy in the Netherlands: A national cohort ...
MERRF, and Lebers Hereditary Optic Atrophy. MenarcheMenarche provides a Carotid disorder consumed in achalasia to a systems ... Mal De DebarquementMal de atrophy Syndrome or MdDs or Disembarkment disease is a gestational million+ which even fund after a ...
References in the ICD-10-CM Index to Diseases and Injuries applicable to the clinical term atrophy, atrophic (of) ... Lebers optic (hereditary) - H47.22 Hereditary optic atrophy. *lip - K13.0 Diseases of lips ... H47.20 Unspecified optic atrophy*glaucomatous - H47.23 Glaucomatous optic atrophy. *hereditary - H47.22 Hereditary optic ... hereditary NEC - G12.1 Other inherited spinal muscular atrophy. *infantile, type I (Werdnig-Hoffmann) - G12.0 Infantile spinal ...
None of the several known mitochondrial DNA mutations associated with Lebers hereditary optic neuropathy (LHON) or with LHON ... keywords = "Dystonia, Hereditary, Mitochondrial disease, Optic atrophy, Putaminal atrophy",. author = "I. Korn-Lubetzki and A. ... None of the several known mitochondrial DNA mutations associated with Lebers hereditary optic neuropathy (LHON) or with LHON ... None of the several known mitochondrial DNA mutations associated with Lebers hereditary optic neuropathy (LHON) or with LHON ...
Lebers Hereditary Optic Atrophy Medicine & Life Sciences 100% * Retinal Ganglion Cells Medicine & Life Sciences 77% ... the subunits of complex I of the mitochondrial electron transport chain are the most common cause of Lebers hereditary optic ... the subunits of complex I of the mitochondrial electron transport chain are the most common cause of Lebers hereditary optic ... the subunits of complex I of the mitochondrial electron transport chain are the most common cause of Lebers hereditary optic ...
Leber hereditary optic neuropathy, Leber optic atrophy and dystonia. Mitochondrial. 21. MT-ND2 Leber hereditary optic ... Leber optic atrophy and dystonia, Mitochondrial complex I deficiency. Mitochondrial. 7. MT-ND4 Leber hereditary optic ... Leber optic atrophy and dystonia, Mitochondrial complex I deficiency. Mitochondrial. 11. MT-ND4L Leber hereditary optic ... Leber hereditary optic neuropathy, Leber optic atrophy and dystonia, Mitochondrial complex I deficiency. Mitochondrial. 16. ...
Methylcobalamin should not be used in patients with early hereditary optic nerve atrophy (Lebers disease). Optic nerve atrophy ... Who should not take this medication? Patients with early hereditary optic nerve atrophy, cyanocobalmin hypersensitivity, and ... Your health care provider needs to know if you have any of these conditions: kidney disease; Lebers disease; megaloblastic ...
Funduscopy revealed bilateral optic atrophy. Routine hematological and biochemical blood tests, including inflammatory markers ... This case report is intended to increase awareness of Leber hereditary optic neuropathy, and highlights the need to consider ... We report the first genetically authenticated Sri Lankan case of Leber hereditary optic neuropathy, illustrating its ... Optical coherence tomography, and the clinical presentation, suggested a diagnosis of Leber hereditary optic neuropathy, which ...
  • The only disease-modifying treatment that has been approved to date is idebenone for the treatment of Leber hereditary optic neuropathy . (nih.gov)
  • Mitochondria in neuroinflammation - Multiple sclerosis (MS), leber hereditary optic neuropathy (LHON) and LHON-MS. (nih.gov)
  • Leber hereditary optic neuropathy (LHON) is an inherited form of vision loss. (medlineplus.gov)
  • Leber's Hereditary Optic Neuropathy with Olivocerebellar Degeneration due to G11778A and T3394C Mutations in the Mitochondrial DNA. (medscape.com)
  • Ornek K, Ornek N. Visual recovery from optic atrophy following acute optic neuropathy in the fellow eye. (medscape.com)
  • Early axonal damage detection by ganglion cell complex analysis with optical coherence tomography in nonarteritic anterior ischaemic optic neuropathy. (medscape.com)
  • Retinal nerve fiber layer evaluation by optical coherence tomography in unaffected carriers with Leber's hereditary optic neuropathy mutations. (medscape.com)
  • Gueven N. Idebenone for Leber's hereditary optic neuropathy. (medscape.com)
  • A randomized placebo-controlled trial of idebenone in Leber's hereditary optic neuropathy. (medscape.com)
  • It is characterized by optic atrophy followed shortly by loss of hearing and peripheral neuropathy. (wikipedia.org)
  • Vision loss in patients with Leber hereditary optic neuropathy typically begins between 15 and 35 years (range, 1 to 80 years). (msdmanuals.com)
  • Some patients with Leber hereditary optic neuropathy have cardiac conduction defects. (msdmanuals.com)
  • If Leber hereditary optic neuropathy is suspected, electrocardiography (ECG) should be done to diagnose occult cardiac conduction defects. (msdmanuals.com)
  • Leber congenital amaurosis is a severe retinal dystrophy and is sometimes known as Leber hereditary optic neuropathy or Leber optic atrophy. (guidedogs.org.uk)
  • Neurogenetic testing for mitochondrial point mutations associated with MELAS, MERFF, and NARP (3243, 8344, 8993) and with Leber's hereditary optic neuropathy (3460, 11778, 14484) were all negative, as was testing for the Friedreich's ataxia triplet expansion. (neurologyindia.com)
  • Leber's hereditary optic neuropathy (LHON) is the maternally inherited mitochondrial disease caused by homoplasmic mutations in the mitochondrial electron transport chain. (tmu.edu.tw)
  • abstract = "Leber{\textquoteright}s hereditary optic neuropathy (LHON) is the maternally inherited mitochondrial disease caused by homoplasmic mutations in the mitochondrial electron transport chain. (tmu.edu.tw)
  • INTRODUCTION: Leber hereditary optic neuropathy is a genetic disease of mitochondrial inheritance characterized by bilateral irreversible vision loss, predominantly affecting males. (bvsalud.org)
  • We report the first genetically authenticated Sri Lankan case of Leber hereditary optic neuropathy, illustrating its characteristic features of male predominance and variable penetrance. (bvsalud.org)
  • CONCLUSIONS: This case report is intended to increase awareness of Leber hereditary optic neuropathy, and highlights the need to consider this rare diagnosis in the appropriate clinical context. (bvsalud.org)
  • It also illustrates the phenomena of incomplete penetrance and male predominance, and suggests the possibility of an X-linked gene governing Leber hereditary optic neuropathy disease expression, which warrants further investigation. (bvsalud.org)
  • Toxic optic neuropathy is a complex, multifactorial disease potentially affecting individuals of all ages, races, places, and economic strata. (springer.com)
  • Typically, toxic and nutritional optic neuropathy is progressive, with bilateral symmetrical painless visual loss causing central or cecocentral scotoma. (springer.com)
  • Epidemic optic neuropathy in Cuba. (springer.com)
  • A, Mean rate of ATP synthesis of digitonin-permeabilized cybrids homoplasmic for the 3 common Leber hereditary optic neuropathy mutations and control cybrids. (jamanetwork.com)
  • Newman NJ Leber's optic neuropathy. (jamanetwork.com)
  • Mitochondrial DNA mutation associated with Leber's hereditary optic neuropathy. (jamanetwork.com)
  • Man PYGriffiths PGBrown DTHowell NTurnbull DMChinnery PF The epidemiology of Leber hereditary optic neuropathy in the North East of England. (jamanetwork.com)
  • Brown MD The enigmatic relationship between mitochondrial dysfunction and Leber's hereditary optic neuropathy. (jamanetwork.com)
  • Leber hereditary optic neuropathy: identification of the same mitochondrial ND1 mutation in six pedigrees. (jamanetwork.com)
  • Smith PRCooper JMGovan GGHarding AESchapira AH Platelet mitochondrial function in Leber's hereditary optic neuropathy. (jamanetwork.com)
  • Leber's hereditary optic neuropathy: biochemical effect of 11778/ND4 and 3460/ND1 mutations and correlation with the mitochondrial genotype. (jamanetwork.com)
  • Cock HRCooper JMSchapira AHV Functional consequences of the 3460-bp mitochondrial DNA mutation associated with Leber's hereditary optic neuropathy. (jamanetwork.com)
  • Grand Rounds: Could Occupational Exposure to n-Hexane and Other Solvents Precipitate Visual Failure in Leber Hereditary Optic Neuropathy? (nih.gov)
  • Leber hereditary optic neuropathy (LHON) is a maternally inherited loss of central vision related to pathogenic mutations in the mitochondrial genome, which are a necessary but not sufficient condition to develop the disease. (nih.gov)
  • After a 6-month period of occupational exposure to n -hexane and other organic solvents, a 27-year-old man (a moderate smoker) developed an optic neuropathy. (nih.gov)
  • The patient suffered a sequential optic neuropathy with the hallmarks of LHON and tested positive for the homoplasmic 11778G → A/ND4 mutation. (nih.gov)
  • Some of the best known mitochondrial diseases are the combination of diabetes mellitus and deafness, Leber's hereditary optic neuropathy, Leigh's disease, pyruvate dehydrogenase complex deficiency and autosomal dominant optic atrophy. (holisticmedicinedevice.com)
  • Leber's hereditary optic neuropathy (LHON) symptoms include eye pain or discomfort, numbness, tingling, and clouding of vision. (globaldata.com)
  • 17, Leo-Kottler B, Luberichs J, Besch D, Christ-Adler M, Fauser S. Leber's hereditary optic neuropathy: clinical and molecular genetic results in a patient with a point mutation at np T11253C (isoleucine to threonine) in the ND4 gene and spontaneous recovery. (chop.edu)
  • 23, Fauser S, Luberichs J, Besch D, Leo-Kottler B. Sequence analysis of the complete mitochondrial genome in patients with Leber's hereditary optic neuropathy lacking the three most common pathogenic DNA mutations. (chop.edu)
  • It remains unclear how these genetic changes cause the death of cells in the optic nerve and lead to the specific features of LHON. (medlineplus.gov)
  • The most common forms are Leber's hereditary optic atrophy (LHON) and autosomal dominant optic atrophy (ADOA). (opticnervenetwork.com)
  • Majander AHuoponen KSavontaus MLNikoskelainen EWikstrom M Electron transfer properties of NADH:ubiquinone reductase in the ND1/3460 and the ND4/11778 mutations of the Leber hereditary optic neuroretinopathy (LHON). (jamanetwork.com)
  • Hereditary optic neuropathies result from genetic defects that cause vision loss and occasionally cardiac or neurologic abnormalities. (msdmanuals.com)
  • It is believed to be the most common of the hereditary optic neuropathies, with prevalence in the range of 1:10,000 to 1:50,000. (msdmanuals.com)
  • This article provides an overview of current knowledge of the genetic causes of hereditary optic neuropathies, and the options and modalities of molecular genetic diagnostic testing, including practical guidelines. (opticnervenetwork.com)
  • Rare diseases leading to the development of blurred vision include hereditary optic neuropathies (dominant optic atrophy, hereditary Leber abiotrophy) and corneal scarring due to vitamin A deficiency. (myallamericancare.com)
  • Carelli VRoss-Cisneros FNSadun AA Mitochondrial dysfunction as a cause of optic neuropathies. (jamanetwork.com)
  • Such visual impairment is not unique to tobacco amblyopia, as it is also seen in neurodegenerative disorders, such as Leber's hereditary optic atrophy (7, 25). (nih.gov)
  • Optic atrophy type 1 (OPA1, or Kjer type optic atrophy) is characterized by bilateral and symmetric optic nerve pallor associated with insidious decrease in visual acuity (usually between ages 4 and 6 years), visual field defects, and color vision defects. (nih.gov)
  • Leber congenital amaurosis (LCA) is an inherited retinal condition. (guidedogs.org.uk)
  • Leber congenital amaurosis can cause sudden painless loss of vision in one or both eyes. (guidedogs.org.uk)
  • Leber congenital amaurosis leads to poor visual function because it affects the optic nerve at the back of the eye. (guidedogs.org.uk)
  • Different types of Leber congenital amaurosis can present with different symptoms. (guidedogs.org.uk)
  • A defect in a number of genes causes Leber congenital amaurosis. (guidedogs.org.uk)
  • Some types of Leber congenital amaurosis remain stable, while others worsen with time, leading to degeneration in eyesight. (guidedogs.org.uk)
  • How is Leber congenital amaurosis diagnosed? (guidedogs.org.uk)
  • Leber congenital amaurosis might be detected at this early stage. (guidedogs.org.uk)
  • The symptoms of Leber congenital amaurosis can be similar to some other diseases, including Loken-Senior syndrome and Joubert syndrome. (guidedogs.org.uk)
  • If your child does have Leber congenital amaurosis, then genetic testing may be used to identify which gene is responsible for the condition. (guidedogs.org.uk)
  • From the age of five years, the child's visual acuity deteriorated, with development of bilateral optic atrophy and pendular nystagmus. (neurologyindia.com)
  • Funduscopy revealed bilateral optic atrophy. (bvsalud.org)
  • Cyanocobalamin has induced severe and rapid optic nerve atrophy in patient's with early Leber's disease. (drugs.com)
  • Patients with early Leber's disease (hereditary optic nerve atrophy) who were treated with cyanocobalamin suffered severe and swift optic atrophy. (americanregent.com)
  • The use of cyanocobalamin is contraindicated in patients with Leber's disease (hereditary optic nerve atrophy). (drugs.com)
  • Patients with early hereditary optic nerve atrophy, cyanocobalamin hypersensitivity, and those who are pregnant. (newbeginningsmedical.com)
  • There are rarer cases of optic atrophy following an autosomal recessive or X-linked recessive mode of inheritance. (opticnervenetwork.com)
  • The optic nerve is continuous at one end with the retina and at the other end with the brain, making it vulnerable to a variety of both ocular and central nervous system (CNS) diseases. (clinicalgate.com)
  • Canine progressive retinal atrophy (PRA) describes a group of hereditary diseases characterized by photoreceptor cell death in the retina, leading to visual impairment. (mdpi.com)
  • Eye Diseases, Hereditary" is a descriptor in the National Library of Medicine's controlled vocabulary thesaurus, MeSH (Medical Subject Headings) . (wakehealth.edu)
  • This graph shows the total number of publications written about "Eye Diseases, Hereditary" by people in this website by year, and whether "Eye Diseases, Hereditary" was a major or minor topic of these publications. (wakehealth.edu)
  • Below are the most recent publications written about "Eye Diseases, Hereditary" by people in Profiles. (wakehealth.edu)
  • Any specific diseases where we specifically need to look for En face images? (eophtha.com)
  • Detailed information on mitochondrial inheritance and Leber's optic atrophy. (uhhospitals.org)
  • Bissell AJ, Yalcinbayir O, Akduman L. Bilateral geographic atrophy: spontaneous visual improvement after loss of vision in the fellow eye. (medscape.com)
  • Pegcetacoplan is in clinical development for the treatment of geographic atrophy of the macula, secondary to age-related macular degeneration (AMD). (nihr.ac.uk)
  • Some patients with AMD will develop geographic atrophy, which is an advanced form of AMD, where cells located in certain regions of the retina waste away leading to blind spots in the visual field. (nihr.ac.uk)
  • Geographic atrophy results in a significant decline in patient quality of life and accounts for 26% of legal blindness in the UK. (nihr.ac.uk)
  • It is thought to be optic abiotrophy, premature degeneration of the optic nerve leading to progressive vision loss. (msdmanuals.com)
  • Most patients with dominant optic atrophy have no associated neurologic abnormalities, although nystagmus and hearing loss have been reported. (msdmanuals.com)
  • The genetic causes of hereditary optic atrophies are complex in terms of the diversity of the involved genes. (opticnervenetwork.com)
  • Optic atrophy occurs in the first year and the following symptoms show up before thirteen years. (wikipedia.org)
  • Besides the common forms of isolated optic atrophies which exclusively affect the visual system, there are a variety of conditions in which the optic atrophy is part of a syndromic disease with additional symptoms that are mostly neurosensory, neurological or neuromuscular. (opticnervenetwork.com)
  • Hereditary optic atrophies are a heterogeneous group of rare degenerative disease affecting the retinal ganglion cells and their axons which form the optic nerve. (opticnervenetwork.com)
  • Recent approvals and new treatment launches, including those of Luxturna for inherited retinal disease (Spark Therapeutics, US approval 2018), Zolgensma for spinal muscular atrophy (Novartis, US approval 2019), and Zynteglo for transfusion-dependent beta-thalassemia (Bluebird Bio, Europe approval 2019), have demonstrated that the theoretical can become actual. (bcg.com)
  • FA is a hereditary disease, caused by a defective gene that can be passed down through a family. (globaldata.com)
  • 4] We present a further patient with sporadic PEID with additional optic atrophy, pendular nystagmus, and migraine with aura, who has been followed-up and investigated over a period of more than 30 years. (neurologyindia.com)
  • Now in her mid thirties, she has residual feelings of left-sided weakness and reduced exercise tolerance, but has no further episodic attacks, and has developed no neurological signs aside from the longstanding optic atrophy and pendular nystagmus. (neurologyindia.com)
  • Diagnosis of dominant optic atrophy and Leber hereditary optic atrophy is mainly clinical. (msdmanuals.com)
  • With an estimated prevalence of 1 : 10 000 to 1 : 20 000, hereditary optic atrophies in their entirety affect about 4000 to 8000 people in Germany. (opticnervenetwork.com)
  • Optic nerve hypoplasia is characterized by a small disc and peripapillary double ring sign, and the inner ring is actually the optic disc margin. (medscape.com)
  • A and B, Longitudinal sections (gross and microscopic, respectively) of the optic nerve (ON) show the intraocular (in the scleral canal) and retrobulbar portions of the ON. (clinicalgate.com)
  • Aniridia also occurs in a hereditary form, usually autosomal dominant. (nih.gov)
  • Ophthalmoscopic examination discloses temporal or diffuse pallor of the optic discs, sometimes associated with optic disc excavation. (nih.gov)