Spastic Paraplegia, Hereditary
Paraplegia
Paraparesis, Spastic
Muscle Spasticity
Pedigree
Adaptor Protein Complex 4
Genes, Dominant
Adenosine Triphosphatases
Paraparesis, Tropical Spastic
Cerebellar Ataxia
Reflex, Babinski
Agenesis of Corpus Callosum
Spasm
Lod Score
Spinal Cord Ischemia
Pelizaeus-Merzbacher Disease
Mutation, Missense
Chromosomes, Human, Pair 2
Cerebral Palsy
Mutation
Human Characteristics
Hereditary Sensory and Motor Neuropathy
Quadriplegia
Optic Atrophy
Age of Onset
Genetic Linkage
Genetic Heterogeneity
Phenotype
Exome
Spinal Cord
Leukocyte L1 Antigen Complex
Spinocerebellar Degenerations
Intellectual Disability
Spinal Cord Injuries
ATP-Dependent Proteases
Myelin Proteolipid Protein
Corpus Callosum
Chromosome Mapping
Heterozygote
Tuberculosis, Spinal
Paraparesis
Aortic Aneurysm, Thoracic
Sex Chromosome Aberrations
Microtubules
Spinal Cord Compression
Motor Neuron Disease
Optic Atrophies, Hereditary
Hydrocephalus
Laminectomy
Magnetic Resonance Imaging
X Chromosome
Neural Conduction
Haplotypes
Chromosomes, Human, Pair 14
Codon, Nonsense
Mitochondrial involvement in Parkinson's disease, Huntington's disease, hereditary spastic paraplegia and Friedreich's ataxia. (1/189)
Respiratory chain dysfunction has been identified in several neurodegenerative disorders. In Friedreich's ataxia (FA) and Huntington's disease (HD), where the respective mutations are in nuclear genes encoding non-respiratory chain mitochondrial proteins, the defects in oxidative phosphorylation are clearly secondary. In Parkinson's disease (PD) the situation is less clear, with some evidence for a primary role of mitochondrial DNA in at least a proportion of patients. The pattern of the respiratory chain defect may provide some clue to its cause; in PD there appears to be a selective complex I deficiency; in HD and FA the deficiencies are most severe in complex II/III with a less severe defect in complex IV. Aconitase activity in HD and FA is severely decreased in brain and muscle, respectively, but appears to be normal in PD brain. Free radical generation is thought to be of importance in both HD and FA, via excitotoxicity in HD and abnormal iron handling in FA. The oxidative damage observed in PD may be secondary to the mitochondrial defect. Whatever the cause(s) and sequence of events, respiratory chain deficiencies appear to play an important role in the pathogenesis of neurodegeneration. The mitochondrial abnormalities induced may converge on the function of the mitochondrion in apoptosis. This mode of cell death is thought to play an important role in neurodegenerative diseases and it is tempting to speculate that the observed mitochondrial defects in PD, HD and FA result directly in apoptotic cell death, or in the lowering of a cell's threshold to undergo apoptosis. Clarifying the role of mitochondria in pathogenesis may provide opportunities for the development of treatments designed to reverse or prevent neurodegeneration. (+info)MR imaging and proton MR spectroscopy in adult Krabbe disease. (2/189)
We present the MR imaging findings in four patients (two pairs of siblings from two unrelated families) with adult Krabbe disease. In the first family, clinical presentation mimicked familial spastic paraplegia. Their MR images showed selective, increased signal intensity on T2-weighted sequences along the corticospinal tracts, most prominently in the proband and barely detectable in her brother. Proton MR spectroscopy showed increased choline and myo-inositol in the affected white matter. In the second family, the clinical presentation differed in that the signs of pyramidal tract involvement were asymmetrical, with concomitant asymmetry on MR images in one. In adults, Krabbe disease may present on MR imaging with selective pyramidal fiber involvement. (+info)Hereditary spastic paraplegia caused by mutations in the SPG4 gene. (3/189)
Autosomal dominant hereditary spastic paraplegia (AD-HSP) is a genetically heterogeneous neurodegenerative disorder characterised by progressive spasticity of the lower limbs. The SPG4 locus at 2p21-p22 accounts for 40-50% of all AD-HSP families. The SPG4 gene was recently identified. It is ubiquitously expressed in adult and foetal tissues and encodes spastin, an ATPase of the AAA family. We have now identified four novel SPG4 mutations in German AD-HSP families, including one large family for which anticipation had been proposed. Mutations include one frame-shift and one missense mutation, both affecting the Walker motif B. Two further mutations affect two donor splice sites in introns 12 and 16, respectively. RT-PCR analysis of both donor splice site mutations revealed exon skipping and reduced stability of aberrantly spliced SPG4 mRNA. All mutations are predicted to cause loss of functional protein. In conclusion, we confirm in German families that SPG4 mutations cause AD-HSP. Our data suggest that SPG4 mutations exert their dominant effect not by gain of function but by haploinsufficiency. If a threshold level of spastin were critical for axonal preservation, such threshold dosage effects might explain the variable expressivity and incomplete penetrance of SPG4-linked AD-HSP. (+info)A refined physical and transcriptional map of the SPG9 locus on 10q23.3-q24.2. (4/189)
Hereditary spastic paraplegia (HSP) is a genetically heterogeneous disorder characterised by progressive spasticity of the lower limbs. Beside 'pure' forms of HSP, 'complicated' forms are reported, where spasticity occurs associated with additional symptoms. We recently described an Italian family with a complicated dominant form of HSP (SPG9) and we mapped the gene responsible to 10q23.3-q24.2, in a 12cM interval between markers D10S564 and D10S603. The phenotypic manifestations in our family are reminiscent of those already described in a smaller British pedigree. We typed individuals from this British family using markers located in the SPG9 critical interval and haplotype reconstruction showed the disorder co-segregating with SPG9. To characterise the SPG9 region better, we constructed a contig of 22 YACs, assigned it to 18 polymorphic markers and positioned 54 ESTs. Furthermore, we searched for ESTs containing a trinucleotide repeat sequence, since anticipation of symptoms was reported in both families. Finally, analysis of a muscle biopsy specimen from one patient was normal, suggesting that, contrary to SPG7, mitochondrial disturbance could not be a primary feature of SPG9. (+info)Genotype-phenotype correlation in inherited brain myelination defects due to proteolipid protein gene mutations. Clinical European Network on Brain Dysmyelinating Disease. (5/189)
Pelizaeus-Merzbacher disease (PMD) and spastic paraplegia type 2 (SPG2) are X-linked developmental defects of myelin formation affecting the central nervous system (CNS). They differ clinically in the onset and severity of the motor disability but both are allelic to the proteolipid protein gene (PLP), which encodes the principal protein components of CNS myelin, PLP and its spliced isoform, DM20. We investigated 52 PMD and 28 SPG families without large PLP duplications or deletions by genomic PCR amplification and sequencing of the PLP gene. We identified 29 and 4 abnormalities respectively. Patients with PLP mutations presented a large range of disease severity, with a continuum between severe forms of PMD, without motor development, to pure forms of SPG. Clinical severity was found to be correlated with the nature of the mutation, suggesting a distinct strategy for detection of PLP point mutations between severe PMD, mild PMD and SPG. Single amino-acid changes in highly conserved regions of the DM20 protein caused the most severe forms of PMD. Substitutions of less conserved amino acids, truncations, absence of the protein and PLP-specific mutations caused the milder forms of PMD and SPG. Therefore, the interactions and stability of the mutated proteins has a major effect on the severity of PLP-related diseases. (+info)Identification and expression analysis of spastin gene mutations in hereditary spastic paraplegia. (6/189)
Pure hereditary spastic paraplegia (SPG) type 4 is the most common form of autosomal dominant hereditary SPG, a neurodegenerative disease characterized primarily by hyperreflexia and progressive spasticity of the lower limbs. It is caused by mutations in the gene encoding spastin, a member of the AAA family of ATPases. We have screened the spastin gene for mutations in 15 families consistent with linkage to the spastin gene locus, SPG4, and have identified 11 mutations, 10 of which are novel. Five of the mutations identified are in noninvariant splice-junction sequences. Reverse transcription-PCR analysis of mRNA from patients shows that each of these five mutations results in aberrant splicing. One mutation was found to be "leaky," or partially penetrant; that is, the mutant allele produced both mutant (skipped exon) and wild-type (full-length) transcripts. This phenomenon was reproduced in in vitro splicing experiments, with a minigene splicing-vector construct only in the context of the endogenous splice junctions flanking the splice junctions of the skipped exon. In the absence of endogenous splice junctions, only mutant transcript was detected. The existence of at least one leaky mutation suggests that relatively small differences in the level of wild-type spastin expression can have significant functional consequences. This may account, at least in part, for the wide ranges in age at onset, symptom severity, and rate of symptom progression that have been reported to occur both among and within families with SPG linked to SPG4. In addition, these results suggest caution in the interpretation of data solely obtained with minigene constructs to study the effects of sequence variation on splicing. The lack of full genomic sequence context in these constructs can mask important functional consequences of the mutation. (+info)The Silver syndrome variant of hereditary spastic paraplegia maps to chromosome 11q12-q14, with evidence for genetic heterogeneity within this subtype. (7/189)
The hereditary spastic paraplegias (HSPs) are a complex group of neurodegenerative disorders characterized by lower-limb spasticity and weakness. Silver syndrome (SS) is a particularly disabling dominantly inherited form of HSP, complicated by amyotrophy of the hand muscles. Having excluded the multiple known HSP loci, we undertook a genomewide screen for linkage of SS in one large multigenerational family, which revealed evidence for linkage of the SS locus, which we have designated "SPG17," to chromosome 11q12-q14. Haplotype construction and analysis of recombination events permitted the minimal interval defining SPG17 to be refined to approximately 13 cM, flanked by markers D11S1765 and D11S4136. SS in a second family was not linked to SPG17, demonstrating further genetic heterogeneity in HSP, even within this clinically distinct subtype. (+info)Survey of human mitochondrial diseases using new genomic/proteomic tools. (8/189)
BACKGROUND: We have constructed Bayesian prior-based, amino-acid sequence profiles for the complete yeast mitochondrial proteome and used them to develop methods for identifying and characterizing the context of protein mutations that give rise to human mitochondrial diseases. (Bayesian priors are conditional probabilities that allow the estimation of the likelihood of an event - such as an amino-acid substitution - on the basis of prior occurrences of similar events.) Because these profiles can assemble sets of taxonomically very diverse homologs, they enable identification of the structurally and/or functionally most critical sites in the proteins on the basis of the degree of sequence conservation. These profiles can also find distant homologs with determined three-dimensional structures that aid in the interpretation of effects of missense mutations. RESULTS: This survey reports such an analysis for 15 missense mutations, one insertion and three deletions involved in Leber's hereditary optic neuropathy, Leigh syndrome, mitochondrial neurogastrointestinal encephalomyopathy, Mohr-Tranebjaerg syndrome, iron-storage disorders related to Friedreich's ataxia, and hereditary spastic paraplegia. We present structural correlations for seven of the mutations. CONCLUSIONS: Of the 19 mutations analyzed, 14 involved changes in very highly conserved parts of the affected proteins. Five out of seven structural correlations provided reasonable explanations for the malfunctions. As additional genetic and structural data become available, this methodology can be extended. It has the potential for assisting in identifying new disease-related genes. Furthermore, profiles with structural homologs can generate mechanistic hypotheses concerning the underlying biochemical processes - and why they break down as a result of the mutations. (+info)Hereditary Spastic Paraplegia (HSP) is a group of genetic disorders that affect the long motor neurons in the spinal cord, leading to lower limb spasticity and weakness. It is characterized by progressive stiffness and contraction of the leg muscles, resulting in difficulty with walking and balance.
The symptoms of HSP typically begin in childhood or early adulthood and worsen over time. The severity of the condition can vary widely, even within the same family, depending on the specific genetic mutation involved. In addition to lower limb spasticity, some individuals with HSP may also experience bladder dysfunction, sensory loss, or other neurological symptoms.
HSP is inherited in an autosomal dominant or autosomal recessive pattern, depending on the specific genetic mutation involved. There are over 70 different genes that have been identified as causing HSP, and genetic testing can be used to confirm the diagnosis and identify the specific genetic mutation responsible.
Treatment for HSP is focused on managing symptoms and maintaining mobility. Physical therapy, orthotics, and medications such as baclofen or tizanidine may be used to help reduce muscle spasticity and improve mobility. In some cases, surgery may be necessary to relieve muscle contractures or other complications.
Paraplegia is a medical condition characterized by partial or complete loss of motor function and sensation in the lower extremities, typically affecting both legs. This results from damage to the spinal cord, often due to trauma such as accidents, falls, or gunshot wounds, or from diseases like spina bifida, polio, or tumors. The specific area and extent of the injury on the spinal cord determine the severity and location of paralysis. Individuals with paraplegia may require assistive devices for mobility, such as wheelchairs, and may face various health challenges, including pressure sores, urinary tract infections, and chronic pain.
Paraparesis, spastic type, is a medical term used to describe a condition characterized by partial weakness or loss of voluntary movement in the lower extremities (legs). The term "paraparesis" comes from Greek words "para" meaning beside or beyond, and "paresis" meaning loosening or relaxation.
In spastic paraparesis, the muscle tone is increased, causing stiffness and resistance to movement, particularly during quick or forceful movements. This increased muscle tone, also known as spasticity, results from an upper motor neuron lesion in the brain or spinal cord that affects the corticospinal tract, which carries signals from the brain to the muscles.
Spastic paraparesis can be caused by various conditions, including spinal cord injuries, multiple sclerosis, hereditary spastic paraplegia, and stroke, among others. The severity of symptoms may vary widely, ranging from mild weakness to complete paralysis. Treatment options for spastic paraparesis depend on the underlying cause and may include physical therapy, medications, surgery, or a combination of these approaches.
Muscle spasticity is a motor disorder characterized by an involuntary increase in muscle tone, leading to stiffness and difficulty in moving muscles. It is often seen in people with damage to the brain or spinal cord, such as those with cerebral palsy, multiple sclerosis, or spinal cord injuries.
In muscle spasticity, the muscles may contract excessively, causing rigid limbs, awkward movements, and abnormal postures. The severity of muscle spasticity can vary from mild stiffness to severe contractures that limit mobility and function.
Muscle spasticity is caused by an imbalance between excitatory and inhibitory signals in the central nervous system, leading to overactivity of the alpha motor neurons that control muscle contraction. This can result in hyperreflexia (overactive reflexes), clonus (rapid, rhythmic muscle contractions), and flexor or extensor spasms.
Effective management of muscle spasticity may involve a combination of physical therapy, medication, surgery, or other interventions to improve function, reduce pain, and prevent complications such as contractures and pressure sores.
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.
Adaptor Protein Complex 4 (AP-4) is a group of proteins that form a complex and play a crucial role in the intracellular trafficking of membrane proteins within eukaryotic cells. The AP-4 complex is composed of four subunits, namely, α-Adaptin, β2-Adaptin, Mu-Adaptin, and Sigmal-Adaptin4 (σ4A or σ4B).
The primary function of the AP-4 complex is to facilitate the sorting of proteins in the trans-Golgi network (TGN) and endosomes. It recognizes specific sorting signals present on the cytoplasmic tails of membrane proteins, recruits accessory proteins, and mediates the formation of transport vesicles that carry these proteins to their target destinations.
Mutations in genes encoding AP-4 complex subunits have been associated with several neurological disorders, including hereditary spastic paraplegia (HSP), mental retardation, and cerebral palsy. These genetic defects disrupt the normal functioning of the AP-4 complex, leading to aberrant protein trafficking and impaired neuronal development and function.
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.
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).
Adenosine triphosphatases (ATPases) are a group of enzymes that catalyze the conversion of adenosine triphosphate (ATP) into adenosine diphosphate (ADP) and inorganic phosphate. This reaction releases energy, which is used to drive various cellular processes such as muscle contraction, transport of ions across membranes, and synthesis of proteins and nucleic acids.
ATPases are classified into several types based on their structure, function, and mechanism of action. Some examples include:
1. P-type ATPases: These ATPases form a phosphorylated intermediate during the reaction cycle and are involved in the transport of ions across membranes, such as the sodium-potassium pump and calcium pumps.
2. F-type ATPases: These ATPases are found in mitochondria, chloroplasts, and bacteria, and are responsible for generating a proton gradient across the membrane, which is used to synthesize ATP.
3. V-type ATPases: These ATPases are found in vacuolar membranes and endomembranes, and are involved in acidification of intracellular compartments.
4. A-type ATPases: These ATPases are found in the plasma membrane and are involved in various functions such as cell signaling and ion transport.
Overall, ATPases play a crucial role in maintaining the energy balance of cells and regulating various physiological processes.
Tropical spastic paraparesis (TSP) is a type of myelopathy (spinal cord disorder) that is associated with chronic infectious or inflammatory conditions. The term "paraparesis" refers to partial weakness in the lower extremities, which is a characteristic feature of TSP.
In Tropical spastic paraparesis, there is a slow and progressive degeneration of the spinal cord, leading to symptoms such as muscle weakness, stiffness, and spasticity (involuntary muscle contractions) in the legs. Other common symptoms include sensory loss, bladder and bowel dysfunction, and sexual impairment.
TSP is often caused by a chronic infection with the human T-lymphotropic virus type 1 (HTLV-1), which is endemic in certain tropical and subtropical regions, including the Caribbean, South America, Central America, Africa, and parts of Asia. The virus is transmitted through blood transfusions, sexual contact, and breastfeeding.
There is no cure for TSP, but symptoms can be managed with physical therapy, medications to relieve muscle spasticity, and other supportive measures. It is important to diagnose and treat TSP early to prevent or slow down the progression of the disease and improve quality of life.
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.
The Babinski reflex, also known as the plantar reflex, is a physiological response that originates from the spinal cord when the sole of the foot is stimulated. It is named after Joseph François Felix Babinski, a French neurologist who described it in 1896.
In a normal, healthy adult, this stimulation typically results in the downward flexion of the big toe and the fanning out of the other toes. However, in infants and young children, as well as in some individuals with certain neurological conditions, the opposite response may occur - the big toe extends upward (dorsiflexes) while the other toes fan out. This is known as the Babinski reflex and can be a sign of damage to the brain or spinal cord, particularly to the nerve pathways that run from the cortex to the spinal cord.
It's important to note that the presence of an extensor plantar response (Babinski reflex) in adults is considered abnormal and may indicate a neurological disorder such as a brain injury, spinal cord injury, multiple sclerosis, or motor neuron disease. However, it's worth mentioning that certain medications, intoxication, or temporary conditions like sleep deprivation can also cause an abnormal plantar response, so further evaluation is necessary to confirm any diagnosis.
Agenesis of the corpus callosum is a birth defect in which the corpus callosum, the part of the brain that connects the two hemispheres and allows them to communicate, fails to develop normally during fetal development. In cases of agenesis of the corpus callosum, the corpus callosum is partially or completely absent.
This condition can vary in severity and may be associated with other brain abnormalities. Some individuals with agenesis of the corpus callosum may have normal intelligence and few symptoms, while others may have intellectual disability, developmental delays, seizures, vision problems, and difficulties with movement and coordination. The exact cause of agenesis of the corpus callosum is not always known, but it can be caused by genetic factors or exposure to certain medications or environmental toxins during pregnancy.
A spasm is a sudden, involuntary contraction or tightening of a muscle, group of muscles, or a hollow organ such as the ureter or bronchi. Spasms can occur as a result of various factors including muscle fatigue, injury, irritation, or abnormal nerve activity. They can cause pain and discomfort, and in some cases, interfere with normal bodily functions. For example, a spasm in the bronchi can cause difficulty breathing, while a spasm in the ureter can cause severe pain and may lead to a kidney stone blockage. The treatment for spasms depends on the underlying cause and may include medication, physical therapy, or lifestyle changes.
A LOD (Logarithm of Odds) score is not a medical term per se, but rather a statistical concept that is used in genetic research and linkage analysis to determine the likelihood of a gene or genetic marker being linked to a particular disease or trait. The LOD score compares the odds of observing the pattern of inheritance of a genetic marker in a family if the marker is linked to the disease, versus the odds if the marker is not linked. A LOD score of 3 or higher is generally considered evidence for linkage, while a score of -2 or lower is considered evidence against linkage.
Spinal cord ischemia refers to a reduction or interruption of blood flow to the spinal cord, leading to insufficient oxygen and nutrient supply. This condition can cause damage to the spinal cord tissue, potentially resulting in neurological deficits, such as muscle weakness, sensory loss, or autonomic dysfunction. Spinal cord ischemia may be caused by various factors, including atherosclerosis, embolism, spinal artery stenosis, or complications during surgery. The severity and extent of the neurological impairment depend on the duration and location of the ischemic event in the spinal cord.
Pelizaeus-Merzbacher disease (PMD) is a rare X-linked recessive genetic disorder affecting the nervous system. It is caused by mutations in the PLP1 gene, which provides instructions for making proteins that are important for the formation and maintenance of the myelin sheath, the protective covering that wraps around nerve cell fibers (axons) in the brain and spinal cord to ensure efficient transmission of electrical signals.
In individuals with PMD, the myelin sheath is either partially or completely absent, leading to progressive neurological symptoms. The classic form of PMD is characterized by early onset of nystagmus (involuntary eye movements), ataxia (loss of muscle coordination and balance), and intellectual disability. Other features may include hypotonia (low muscle tone), spasticity (stiff or rigid muscles), and seizures. The severity and progression of the disease can vary widely among affected individuals, ranging from a severe, lethal form to a milder form with a slower disease course.
Currently, there is no cure for PMD, and treatment is focused on managing symptoms and improving quality of life.
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.
Human chromosome pair 2 consists of two rod-shaped structures present in the nucleus of each cell of the human body. Each member of the pair contains thousands of genes and other genetic material, encoded in the form of DNA molecules. Chromosomes are the physical carriers of inheritance, and human cells typically contain 23 pairs of chromosomes for a total of 46 chromosomes.
Chromosome pair 2 is one of the autosomal pairs, meaning that it is not a sex chromosome (X or Y). Each member of chromosome pair 2 is approximately 247 million base pairs in length and contains an estimated 1,000-1,300 genes. These genes play crucial roles in various biological processes, including development, metabolism, and response to environmental stimuli.
Abnormalities in chromosome pair 2 can lead to genetic disorders, such as cat-eye syndrome (CES), which is characterized by iris abnormalities, anal atresia, hearing loss, and intellectual disability. This disorder arises from the presence of an extra copy of a small region on chromosome 2, resulting in partial trisomy of this region. Other genetic conditions associated with chromosome pair 2 include proximal 2q13.3 microdeletion syndrome and Potocki-Lupski syndrome (PTLS).
Cerebral palsy (CP) is a group of disorders that affect a person's ability to move and maintain balance and posture. According to the Mayo Clinic, CP is caused by abnormal brain development or damage to the developing brain that affects a child's ability to control movement.
The symptoms of cerebral palsy can vary in severity and may include:
* Spasticity (stiff or tight muscles)
* Rigidity (resistance to passive movement)
* Poor coordination and balance
* Weakness or paralysis
* Tremors or involuntary movements
* Abnormal gait or difficulty walking
* Difficulty with fine motor skills, such as writing or using utensils
* Speech and language difficulties
* Vision, hearing, or swallowing problems
It's important to note that cerebral palsy is not a progressive condition, meaning that it does not worsen over time. However, the symptoms may change over time, and some individuals with CP may experience additional medical conditions as they age.
Cerebral palsy is usually caused by brain damage that occurs before or during birth, but it can also be caused by brain injuries that occur in the first few years of life. Some possible causes of cerebral palsy include:
* Infections during pregnancy
* Lack of oxygen to the brain during delivery
* Traumatic head injury during birth
* Brain bleeding or stroke in the newborn period
* Genetic disorders
* Maternal illness or infection during pregnancy
There is no cure for cerebral palsy, but early intervention and treatment can help improve outcomes and quality of life. Treatment may include physical therapy, occupational therapy, speech therapy, medications to manage symptoms, surgery, and assistive devices such as braces or wheelchairs.
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.
I'm sorry for any confusion, but "human characteristics" is not a medical term or concept. It refers to the typical traits, attributes, and features that define humans as a species, both physically and behaviorally. Physical human characteristics include bipedal locomotion, large brains, and fine motor skills, while behavioral characteristics can include complex language use, self-awareness, and sociality.
However, if you have any specific medical or health-related questions, I would be happy to help answer them to the best of my ability!
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.
Quadriplegia, also known as tetraplegia, is a medical condition characterized by paralysis affecting all four limbs and the trunk of the body. It results from damage to the cervical spinal cord, typically at levels C1-C8, which controls signals to the muscles in the arms, hands, trunk, legs, and pelvic organs. The extent of quadriplegia can vary widely, ranging from weakness to complete loss of movement and sensation below the level of injury. Other symptoms may include difficulty breathing, bowel and bladder dysfunction, and sexual dysfunction. The severity and prognosis depend on the location and extent of the spinal cord injury.
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.
The "age of onset" is a medical term that refers to the age at which an individual first develops or displays symptoms of a particular disease, disorder, or condition. It can be used to describe various medical conditions, including both physical and mental health disorders. The age of onset can have implications for prognosis, treatment approaches, and potential causes of the condition. In some cases, early onset may indicate a more severe or progressive course of the disease, while late-onset symptoms might be associated with different underlying factors or etiologies. It is essential to provide accurate and precise information regarding the age of onset when discussing a patient's medical history and treatment plan.
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.
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 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.
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.
The exome is the part of the genome that contains all the protein-coding regions. It represents less than 2% of the human genome but accounts for about 85% of disease-causing mutations. Exome sequencing, therefore, is a cost-effective and efficient method to identify genetic variants associated with various diseases, including cancer, neurological disorders, and inherited genetic conditions.
The spinal cord is a major part of the nervous system, extending from the brainstem and continuing down to the lower back. It is a slender, tubular bundle of nerve fibers (axons) and support cells (glial cells) that carries signals between the brain and the rest of the body. The spinal cord primarily serves as a conduit for motor information, which travels from the brain to the muscles, and sensory information, which travels from the body to the brain. It also contains neurons that can independently process and respond to information within the spinal cord without direct input from the brain.
The spinal cord is protected by the bony vertebral column (spine) and is divided into 31 segments: 8 cervical, 12 thoracic, 5 lumbar, 5 sacral, and 1 coccygeal. Each segment corresponds to a specific region of the body and gives rise to pairs of spinal nerves that exit through the intervertebral foramina at each level.
The spinal cord is responsible for several vital functions, including:
1. Reflexes: Simple reflex actions, such as the withdrawal reflex when touching a hot surface, are mediated by the spinal cord without involving the brain.
2. Muscle control: The spinal cord carries motor signals from the brain to the muscles, enabling voluntary movement and muscle tone regulation.
3. Sensory perception: The spinal cord transmits sensory information, such as touch, temperature, pain, and vibration, from the body to the brain for processing and awareness.
4. Autonomic functions: The sympathetic and parasympathetic divisions of the autonomic nervous system originate in the thoracolumbar and sacral regions of the spinal cord, respectively, controlling involuntary physiological responses like heart rate, blood pressure, digestion, and respiration.
Damage to the spinal cord can result in various degrees of paralysis or loss of sensation below the level of injury, depending on the severity and location of the damage.
The Leukocyte L1 Antigen Complex, also known as CD58 or LFA-3 (Lymphocyte Function-Associated Antigen 3), is not a single entity but rather a glycoprotein found on the surface of various cells in the human body, including leukocytes (white blood cells). It plays a crucial role in the immune system's response by interacting with the CD2 receptor on T-cells and natural killer (NK) cells. This interaction helps facilitate cell-to-cell adhesion and activation of T-cells, which are essential for an effective immune response against infections and cancer.
The Leukocyte L1 Antigen Complex is often targeted by certain viruses to evade the host's immune system. For example, some strains of HIV (Human Immunodeficiency Virus) can downregulate the expression of this protein on infected cells, making it harder for the immune system to recognize and eliminate them.
It is important to note that while "Leukocyte L1 Antigen Complex" refers to a specific cell surface protein, CD58 or LFA-3 are alternative names used in the scientific literature to refer to this same protein.
Spinocerebellar degenerations (SCDs) are a group of genetic disorders that primarily affect the cerebellum, the part of the brain responsible for coordinating muscle movements, and the spinal cord. These conditions are characterized by progressive degeneration or loss of nerve cells in the cerebellum and/or spinal cord, leading to various neurological symptoms.
SCDs are often inherited in an autosomal dominant manner, meaning that only one copy of the altered gene from either parent is enough to cause the disorder. The most common type of SCD is spinocerebellar ataxia (SCA), which includes several subtypes (SCA1, SCA2, SCA3, etc.) differentiated by their genetic causes and specific clinical features.
Symptoms of spinocerebellar degenerations may include:
1. Progressive ataxia (loss of coordination and balance)
2. Dysarthria (speech difficulty)
3. Nystagmus (involuntary eye movements)
4. Oculomotor abnormalities (problems with eye movement control)
5. Tremors or other involuntary muscle movements
6. Muscle weakness and spasticity
7. Sensory disturbances, such as numbness or tingling sensations
8. Dysphagia (difficulty swallowing)
9. Cognitive impairment in some cases
The age of onset, severity, and progression of symptoms can vary significantly among different SCD subtypes and individuals. Currently, there is no cure for spinocerebellar degenerations, but various supportive treatments and therapies can help manage symptoms and improve quality of life.
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.
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.
Spinal cord injuries (SCI) refer to damage to the spinal cord that results in a loss of function, such as mobility or feeling. This injury can be caused by direct trauma to the spine or by indirect damage resulting from disease or degeneration of surrounding bones, tissues, or blood vessels. The location and severity of the injury on the spinal cord will determine which parts of the body are affected and to what extent.
The effects of SCI can range from mild sensory changes to severe paralysis, including loss of motor function, autonomic dysfunction, and possible changes in sensation, strength, and reflexes below the level of injury. These injuries are typically classified as complete or incomplete, depending on whether there is any remaining function below the level of injury.
Immediate medical attention is crucial for spinal cord injuries to prevent further damage and improve the chances of recovery. Treatment usually involves immobilization of the spine, medications to reduce swelling and pressure, surgery to stabilize the spine, and rehabilitation to help regain lost function. Despite advances in treatment, SCI can have a significant impact on a person's quality of life and ability to perform daily activities.
ATP-dependent proteases are a type of protein complex that play a crucial role in maintaining cellular homeostasis by breaking down damaged or misfolded proteins. They use the energy from ATP (adenosine triphosphate) hydrolysis to unfold and degrade these proteins into smaller peptides or individual amino acids, which can then be recycled or disposed of by the cell.
These proteases are essential for a variety of cellular processes, including protein quality control, regulation of cell signaling pathways, and clearance of damaged organelles. They are also involved in various cellular responses to stress, such as the unfolded protein response (UPR) and autophagy.
There are several different types of ATP-dependent proteases, including the 26S proteasome, which is responsible for degrading most intracellular proteins, and the Clp/Hsp100 family of proteases, which are involved in protein folding and disaggregation. Dysregulation of ATP-dependent proteases has been implicated in various diseases, including neurodegenerative disorders, cancer, and infectious diseases.
Myelin Proteolipid Protein (PLP) is a major component of the myelin sheath, which is a fatty insulating substance that covers and protects nerve fibers in the central nervous system (CNS). PLP makes up about 50% of the proteins found in the myelin sheath. It plays a crucial role in the structure and function of the myelin sheath, including maintaining its compactness and stability. Defects or mutations in the gene that encodes for PLP can lead to various demyelinating diseases, such as X-linked adrenoleukodystrophy (X-ALD) and Pelizaeus-Merzbacher disease (PMD), which are characterized by the degeneration of the myelin sheath and subsequent neurological impairments.
The corpus callosum is the largest collection of white matter in the brain, consisting of approximately 200 million nerve fibers. It is a broad, flat band of tissue that connects the two hemispheres of the brain, allowing them to communicate and coordinate information processing. The corpus callosum plays a crucial role in integrating sensory, motor, and cognitive functions between the two sides of the brain. Damage to the corpus callosum can result in various neurological symptoms, including difficulties with movement, speech, memory, and social behavior.
Chromosome mapping, also known as physical mapping, is the process of determining the location and order of specific genes or genetic markers on a chromosome. This is typically done by using various laboratory techniques to identify landmarks along the chromosome, such as restriction enzyme cutting sites or patterns of DNA sequence repeats. The resulting map provides important information about the organization and structure of the genome, and can be used for a variety of purposes, including identifying the location of genes associated with genetic diseases, studying evolutionary relationships between organisms, and developing genetic markers for use in breeding or forensic applications.
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.
A heterozygote is an individual who has inherited two different alleles (versions) of a particular gene, one from each parent. This means that the individual's genotype for that gene contains both a dominant and a recessive allele. The dominant allele will be expressed phenotypically (outwardly visible), while the recessive allele may or may not have any effect on the individual's observable traits, depending on the specific gene and its function. Heterozygotes are often represented as 'Aa', where 'A' is the dominant allele and 'a' is the recessive allele.
Motor neurons are specialized nerve cells in the brain and spinal cord that play a crucial role in controlling voluntary muscle movements. They transmit electrical signals from the brain to the muscles, enabling us to perform actions such as walking, talking, and swallowing. There are two types of motor neurons: upper motor neurons, which originate in the brain's motor cortex and travel down to the brainstem and spinal cord; and lower motor neurons, which extend from the brainstem and spinal cord to the muscles. Damage or degeneration of these motor neurons can lead to various neurological disorders, such as amyotrophic lateral sclerosis (ALS) and spinal muscular atrophy (SMA).
Metalloendopeptidases are a type of enzymes that cleave peptide bonds in proteins, specifically at interior positions within the polypeptide chain. They require metal ions as cofactors for their catalytic activity, typically zinc (Zn2+) or cobalt (Co2+). These enzymes play important roles in various biological processes such as protein degradation, processing, and signaling. Examples of metalloendopeptidases include thermolysin, matrix metalloproteinases (MMPs), and neutrophil elastase.
Tuberculosis (TB) of the spine, also known as Pott's disease, is a specific form of extrapulmonary tuberculosis that involves the vertebral column. It is caused by the Mycobacterium tuberculosis bacterium, which primarily affects the lungs but can spread through the bloodstream to other parts of the body, including the spine.
In Pott's disease, the infection leads to the destruction of the spongy bone (vertebral body) and the intervertebral disc space, resulting in vertebral collapse, kyphosis (hunchback deformity), and potential neurological complications due to spinal cord compression. Common symptoms include back pain, stiffness, fever, night sweats, and weight loss. Early diagnosis and treatment with a multidrug antibiotic regimen are crucial to prevent long-term disability and further spread of the infection.
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.
Paraparesis is a medical term that refers to a mild to moderate form of paralysis affecting the lower limbs, specifically the legs. It is characterized by partial loss of strength and mobility, which may result in difficulty walking or maintaining balance. Paraparesis can be caused by various conditions such as spinal cord injuries, multiple sclerosis, spina bifida, or other neurological disorders affecting the spinal cord.
The term "para" means "two," and "paresis" comes from the Greek word "paresis," which means "loosening" or "relaxation." Therefore, paraparesis implies weakness or partial paralysis in two lower extremities. It is important to note that while paraparesis can impact a person's ability to walk and perform daily activities, it does not necessarily lead to complete loss of movement or sensation in the affected limbs.
Proper diagnosis and management of the underlying cause are crucial for improving symptoms and preventing further progression of paraparesis. Treatment options may include physical therapy, medications, assistive devices, or surgical interventions depending on the specific condition causing the paraparesis.
A thoracic aortic aneurysm is a localized dilatation or bulging of the thoracic aorta, which is the part of the aorta that runs through the chest cavity. The aorta is the largest artery in the body, and it carries oxygenated blood from the heart to the rest of the body.
Thoracic aortic aneurysms can occur anywhere along the thoracic aorta, but they are most commonly found in the aortic arch or the descending thoracic aorta. These aneurysms can vary in size, and they are considered significant when they are 50% larger than the expected normal diameter of the aorta.
The exact cause of thoracic aortic aneurysms is not fully understood, but several factors can contribute to their development, including:
* Atherosclerosis (hardening and narrowing of the arteries)
* High blood pressure
* Genetic disorders such as Marfan syndrome or Ehlers-Danlos syndrome
* Infections or inflammation of the aorta
* Trauma to the chest
Thoracic aortic aneurysms can be asymptomatic and found incidentally on imaging studies, or they may present with symptoms such as chest pain, cough, difficulty swallowing, or hoarseness. If left untreated, thoracic aortic aneurysms can lead to serious complications, including aortic dissection (tearing of the inner layer of the aorta) or rupture, which can be life-threatening.
Treatment options for thoracic aortic aneurysms include medical management with blood pressure control and cholesterol-lowering medications, as well as surgical repair or endovascular stenting, depending on the size, location, and growth rate of the aneurysm. Regular follow-up imaging is necessary to monitor the size and progression of the aneurysm over time.
An axon is a long, slender extension of a neuron (a type of nerve cell) that conducts electrical impulses (nerve impulses) away from the cell body to target cells, such as other neurons or muscle cells. Axons can vary in length from a few micrometers to over a meter long and are typically surrounded by a myelin sheath, which helps to insulate and protect the axon and allows for faster transmission of nerve impulses.
Axons play a critical role in the functioning of the nervous system, as they provide the means by which neurons communicate with one another and with other cells in the body. Damage to axons can result in serious neurological problems, such as those seen in spinal cord injuries or neurodegenerative diseases like multiple sclerosis.
Sex chromosome aberrations refer to structural and numerical abnormalities in the sex chromosomes, which are typically represented as X and Y chromosomes in humans. These aberrations can result in variations in the number of sex chromosomes, such as Klinefelter syndrome (47,XXY), Turner syndrome (45,X), and Jacobs/XYY syndrome (47,XYY). They can also include structural changes, such as deletions, duplications, or translocations of sex chromosome material.
Sex chromosome aberrations may lead to a range of phenotypic effects, including differences in physical characteristics, cognitive development, fertility, and susceptibility to certain health conditions. The manifestation and severity of these impacts can vary widely depending on the specific type and extent of the aberration, as well as individual genetic factors and environmental influences.
It is important to note that while sex chromosome aberrations may pose challenges and require medical management, they do not inherently define or limit a person's potential, identity, or worth. Comprehensive care, support, and education can help individuals with sex chromosome aberrations lead fulfilling lives and reach their full potential.
Microtubules are hollow, cylindrical structures composed of tubulin proteins in the cytoskeleton of eukaryotic cells. They play crucial roles in various cellular processes such as maintaining cell shape, intracellular transport, and cell division (mitosis and meiosis). Microtubules are dynamic, undergoing continuous assembly and disassembly, which allows them to rapidly reorganize in response to cellular needs. They also form part of important cellular structures like centrioles, basal bodies, and cilia/flagella.
Spinal cord compression is a medical condition that refers to the narrowing of the spinal canal, which puts pressure on the spinal cord and the nerves that branch out from it. This can occur due to various reasons such as degenerative changes in the spine, herniated discs, bone spurs, tumors, or fractures. The compression can lead to a range of symptoms including pain, numbness, tingling, weakness, or loss of bladder and bowel control. In severe cases, it can cause paralysis. Treatment options depend on the underlying cause and may include physical therapy, medication, surgery, or radiation therapy.
Motor Neuron Disease (MND) is a progressive neurodegenerative disorder that affects the motor neurons, which are nerve cells in the brain and spinal cord responsible for controlling voluntary muscles involved in movement, speaking, breathing, and swallowing. As the motor neurons degenerate and die, they stop sending signals to the muscles, causing them to weaken, waste away (atrophy), and eventually lead to paralysis.
There are several types of MND, including:
1. Amyotrophic Lateral Sclerosis (ALS): Also known as Lou Gehrig's disease, this is the most common form of MND. It affects both upper and lower motor neurons, causing muscle weakness, stiffness, twitching, and atrophy throughout the body.
2. Progressive Bulbar Palsy (PBP): This type primarily affects the bulbar muscles in the brainstem, which control speech, swallowing, and chewing. Patients with PBP experience difficulties with speaking, slurred speech, and problems swallowing and may also have weak facial muscles and limb weakness.
3. Primary Lateral Sclerosis (PLS): This form of MND affects only the upper motor neurons, causing muscle stiffness, spasticity, and weakness, primarily in the legs. PLS progresses more slowly than ALS, and patients usually maintain their ability to speak and swallow for a longer period.
4. Progressive Muscular Atrophy (PMA): This type of MND affects only the lower motor neurons, causing muscle wasting, weakness, and fasciculations (muscle twitches). PMA progresses more slowly than ALS but can still be severely disabling over time.
5. Spinal Muscular Atrophy (SMA): This is a genetic form of MND that typically presents in infancy or childhood, although adult-onset forms exist. SMA affects the lower motor neurons in the spinal cord, causing muscle weakness and atrophy, primarily in the legs and trunk.
The exact cause of Motor Neuron Disease is not fully understood, but it is believed to involve a combination of genetic, environmental, and lifestyle factors. There is currently no cure for MND, and treatment focuses on managing symptoms, maintaining quality of life, and slowing disease progression through various therapies and medications.
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.
Hydrocephalus is a medical condition characterized by an abnormal accumulation of cerebrospinal fluid (CSF) within the brain, leading to an increase in intracranial pressure and potentially causing damage to the brain tissues. This excessive buildup of CSF can result from either overproduction or impaired absorption of the fluid, which typically causes the ventricles (fluid-filled spaces) inside the brain to expand and put pressure on surrounding brain structures.
The condition can be congenital, present at birth due to genetic factors or abnormalities during fetal development, or acquired later in life as a result of injuries, infections, tumors, or other disorders affecting the brain's ability to regulate CSF flow and absorption. Symptoms may vary depending on age, severity, and duration but often include headaches, vomiting, balance problems, vision issues, cognitive impairment, and changes in behavior or personality.
Treatment for hydrocephalus typically involves surgically implanting a shunt system that diverts the excess CSF from the brain to another part of the body where it can be absorbed, such as the abdominal cavity. In some cases, endoscopic third ventriculostomy (ETV) might be an alternative treatment option, creating a new pathway for CSF flow within the brain. Regular follow-ups with neurosurgeons and other healthcare professionals are essential to monitor the condition and make any necessary adjustments to the treatment plan.
A laminectomy is a surgical procedure that involves the removal of the lamina, which is the back part of the vertebra that covers the spinal canal. This procedure is often performed to relieve pressure on the spinal cord or nerves caused by conditions such as herniated discs, spinal stenosis, or tumors. By removing the lamina, the surgeon can access the affected area and alleviate the compression on the spinal cord or nerves, thereby reducing pain, numbness, or weakness in the back, legs, or arms.
Laminectomy may be performed as a standalone procedure or in combination with other surgical techniques such as discectomy, foraminotomy, or spinal fusion. The specific approach and extent of the surgery will depend on the patient's individual condition and symptoms.
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.
The X chromosome is one of the two types of sex-determining chromosomes in humans (the other being the Y chromosome). It's one of the 23 pairs of chromosomes that make up a person's genetic material. Females typically have two copies of the X chromosome (XX), while males usually have one X and one Y chromosome (XY).
The X chromosome contains hundreds of genes that are responsible for the production of various proteins, many of which are essential for normal bodily functions. Some of the critical roles of the X chromosome include:
1. Sex Determination: The presence or absence of the Y chromosome determines whether an individual is male or female. If there is no Y chromosome, the individual will typically develop as a female.
2. Genetic Disorders: Since females have two copies of the X chromosome, they are less likely to be affected by X-linked genetic disorders than males. Males, having only one X chromosome, will express any recessive X-linked traits they inherit.
3. Dosage Compensation: To compensate for the difference in gene dosage between males and females, a process called X-inactivation occurs during female embryonic development. One of the two X chromosomes is randomly inactivated in each cell, resulting in a single functional copy per cell.
The X chromosome plays a crucial role in human genetics and development, contributing to various traits and characteristics, including sex determination and dosage compensation.
Neural conduction is the process by which electrical signals, known as action potentials, are transmitted along the axon of a neuron (nerve cell) to transmit information between different parts of the nervous system. This electrical impulse is generated by the movement of ions across the neuronal membrane, and it propagates down the length of the axon until it reaches the synapse, where it can then stimulate the release of neurotransmitters to communicate with other neurons or target cells. The speed of neural conduction can vary depending on factors such as the diameter of the axon, the presence of myelin sheaths (which act as insulation and allow for faster conduction), and the temperature of the environment.
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.
Human chromosome pair 14 consists of two rod-shaped structures present in the nucleus of human cells, which contain genetic material in the form of DNA and proteins. Each member of the pair contains a single very long DNA molecule that carries an identical set of genes and other genetic elements, totaling approximately 105 million base pairs. These chromosomes play a crucial role in the development, functioning, and reproduction of human beings.
Chromosome 14 is one of the autosomal chromosomes, meaning it is not involved in determining the sex of an individual. It contains around 800-1,000 genes that provide instructions for producing various proteins responsible for numerous cellular functions and processes. Some notable genes located on chromosome 14 include those associated with neurodevelopmental disorders, cancer susceptibility, and immune system regulation.
Human cells typically have 23 pairs of chromosomes, including 22 autosomal pairs (numbered 1-22) and one pair of sex chromosomes (XX for females or XY for males). Chromosome pair 14 is the eighth largest autosomal pair in terms of its total length.
It's important to note that genetic information on chromosome 14, like all human chromosomes, can vary between individuals due to genetic variations and mutations. These differences contribute to the unique characteristics and traits found among humans.
Equinus deformity is a condition in which the ankle remains in a permanently plantarflexed position, meaning that the toes are pointing downward. This limitation in motion can occur in one or both feet and can be congenital (present at birth) or acquired. Acquired equinus deformity can result from conditions such as cerebral palsy, stroke, trauma, or prolonged immobilization. The limited range of motion in the ankle can cause difficulty walking, pain, and abnormalities in gait. Treatment options for equinus deformity may include physical therapy, bracing, orthotic devices, or surgery.
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.
Human chromosome pair 15 consists of two rod-shaped structures present in the nucleus of each cell in the human body. Each chromosome is made up of DNA tightly coiled around histone proteins, forming a complex structure called a chromatin.
Chromosomes come in pairs, with one chromosome inherited from each parent. Chromosome pair 15 includes two homologous chromosomes, meaning they have the same size, shape, and gene content but may contain slight variations in their DNA sequences.
These chromosomes play a crucial role in inheritance and the development and function of the human body. Chromosome pair 15 contains around 100 million base pairs of DNA and approximately 700 protein-coding genes, which are involved in various biological processes such as growth, development, metabolism, and regulation of gene expression.
Abnormalities in chromosome pair 15 can lead to genetic disorders, including Prader-Willi syndrome and Angelman syndrome, which are caused by the loss or alteration of specific regions on chromosome 15.
Hereditary spastic paraplegia
Roman Polianskyi
Warburg Micro syndrome
PLA2G6
Riin Tamm
UBAP1
Machado-Joseph disease
L1 syndrome
Kufor-Rakeb syndrome
ZFYVE27
SPG20
Spastic paraplegia 6
Ohad Birk
Spastin
NIPA1
KIF5A
KCNA2
KIF1C
REEP2
Atlastin-1
ZFYVE26
KIAA0196
SPG23
FA2H
GJC2
Spastic paraplegia 31
Mitochondrion
RIPK5
Vesicular transport adaptor protein
Mary Reilly (academic)
Hereditary spastic paraplegia - Wikipedia
Hereditary Spastic Paraplegia: Practice Essentials, Etiology, Epidemiology
Hereditary Spastic Paraplegia (HSP): Facts and Information
TSRI study points way to potential therapies for hereditary spastic paraplegia
A locus for autosomal dominant 'pure' hereditary spastic paraplegia maps to chromosome 19q13
Hereditary spastic paraplegia 2 AND humans[mesh] AND review[publication type] - Search Results - PubMed
Leukodystrophy mimicking hereditary spastic paraplegia - NDT | NDT
Pattern visual evoked responses in hereditary spastic paraplegia | Journal of Neurology, Neurosurgery & Psychiatry
Hereditary Spastic Paraplegia: Practice Essentials, Etiology, Epidemiology
MiR-33a is a therapeutic target in SPG4-related hereditary spastic paraplegia human neurons | Clinical Science | Portland Press
Hereditary Spastic Paraplegia Differential Diagnoses
Electrophysiological characterisation of motor and sensory tracts in patients with hereditary spastic paraplegia (HSP) |...
GPT2 mutations cause developmental encephalopathy with microcephaly and features of complicated hereditary spastic paraplegia
COVID-19 reveals influence of physical activity on symptom severity in hereditary spastic paraplegia
Hereditary Spastic Paraplegia: Background, Etiology, Epidemiology
Hereditary Spastic Paraplegia Precision Panel - Italy
The role of hereditary spastic paraplegia related genes in multiple sclerosis - Nuffield Department of Clinical Neurosciences
Hereditary Spastic Paraplegia - Neurologic Disorders - MSD Manual Professional Edition
Hereditary spastic paraplegia 6 (Concept Id: C1838192) - MedGen - NCBI
Study groups & networks - Hereditary Spastic Paraplegias - ERN-RND | European Reference Network on Rare Neurological Diseases
Investigating Common Pathogenic Mechanisms Of Rare Genetic Hereditary Spastic Paraplegia
SPINAL SOMATOSENSORY EVOKED-POTENTIALS IN HEREDITARY SPASTIC PARAPLEGIA - Oxford Neuroscience
Diagnosis to Community: Hereditary Spastic Paraplegia SPG 7 - Global Genes
The role of the kinesin motor KIF1C in hereditary spastic paraplegia
Anti-spastic therapies in Hereditary Spastic Paraplegia - European Reference Network - EURO-NMD
Optic Atrophy and Hereditary Spastic Paraplegia via the SPG7 Gene Test - PreventionGenetics
Alteration of ornithine metabolism leads to dominant and recessive hereditary spastic paraplegia
A novel heterozygous variant in ERLIN2 causes autosomal dominant pure hereditary spastic paraplegia.
Spastic paraplegia type 4: MedlinePlus Genetics
Spastic paraplegia, optic atrophy, and neuropathy is linked to chromosome 11q13 | Hereditary Ocular Diseases
Thin corpus callosum3
- Mutations in SPG11, encoding spatacsin, are a major cause of spastic paraplegia with thin corpus callosum. (medscape.com)
- Kjellin syndrome is characterized by retinal degeneration, autosomal recessive hereditary spastic paraplegia, and thin corpus callosum initially associated with spastic paraplegia 15 (SPG15) but more often occurring in individuals with SPG11. (nih.gov)
- The inheritance of Kjellin's syndrome is autosomal recessive, and the syndrome is characterized by spastic paraplegia, mental retardation, amyotrophy, thin corpus callosum, and macular dystrophy ( 2 2 Webb S, Patterson V, Hutchinson M. Two families with autosomal recessive spastic paraplegia, pigmented maculopathy, and dementia. (scielo.br)
Paraparesis7
- HSP is also known as hereditary spastic paraparesis, familial spastic paraplegia, French settlement disease, Strumpell disease, or Strumpell-Lorrain disease. (wikipedia.org)
- [ 4 ] HSP is also called familial spastic paraparesis and Strümpell-Lorrain syndrome. (medscape.com)
- Whereas all patients showed clinical signs of spastic paraparesis, MEPs were normal in 27% of patients and revealed a broad spectrum with axonal or demyelinating features in the others. (biomedcentral.com)
- Diagnostic criteria for HSP included (i) spastic paraparesis or spastic tetraparesis with legs earlier and more severely affected than arms or (ii) spastic paraparesis as early and prominent sign of a neurodegenerative multisystem disease after exclusion of other causes. (biomedcentral.com)
- To exclude secondary forms of spastic paraparesis standard diagnostic procedures covered MRI of head and spine, vitamin B12 and folic acid levels, very long chain fatty acids (VLCFA), neurometabolic screening (Krabbe disease, metachromatic leukodystrophy, GM1-gangliosidosis, GM2-gangliosidoses Tay Sachs and Sandhoff, Gaucher disease) and cerebrospinal fluid analysis. (biomedcentral.com)
- A 34-year-old white male was admitted to São Paulo University Hospital in Ribeirão Preto, for investigation of spastic paraparesis. (scielo.br)
- We report the genetic detection of B. valaisiana in the CSF of a 61-year-old man with a history of spastic paraparesis, which is strong clinical evidence of advanced neuroborreliosis. (cdc.gov)
Spasticity11
- Despite this, some of the same anti-spasticity medications used in spastic cerebral palsy are sometimes used to treat HSP symptoms. (wikipedia.org)
- Hereditary spastic paraplegia (HSP) is a syndrome designation describing inherited disorders in which lower extremity weakness and spasticity are the predominant symptoms. (nih.gov)
- Hereditary spastic paraplegias (HSPs) are characterised by lower limb spasticity due to degeneration of the corticospinal tract. (biomedcentral.com)
- Hereditary spastic paraplegias (HSPs) encompass a group of neurodegenerative disorders with lower limb spasticity due to degeneration of the corticospinal tract as most prominent sign. (biomedcentral.com)
- A form of hereditary spastic paraplegia which usually presents in late adolescence or early adulthood as a pure phenotype of lower limb spasticity with hyperreflexia and extensor plantar responses, as well as mild bladder disturbances and pes cavus. (nih.gov)
- Clinically and genetically heterogeneous hereditary spastic paraplegia (HSP) is a group of disorders in which primary symptom is insidiously progressive spasticity (rigid muscles) and weakness of the lower limbs. (preventiongenetics.com)
- Like all hereditary spastic paraplegias, spastic paraplegia type 4 involves spasticity of the leg muscles and muscle weakness. (medlineplus.gov)
- HSP-SPAST is the most common form of hereditary spastic paraplegia (HSP), a neurodegenerative disease causing lower limb spasticity. (garvan.org.au)
- Hereditary spastic paraplegia (HSP) is characterized by weakness and spasticity of the lower extremities. (scielo.br)
- Hereditary spastic paraplegia (HSP) is a clinically and genetically heterogeneous group of diseases involving weakness and spasticity of the lower extremities combined with additional neurological or non-neurological manifestations ( 1 1 Finsterer J, Loscher W, Quasthoff S, Wanschitz J, Auer-Grumbach M, Stevanin G. Hereditary spastic paraplegias with autosomal dominant, recessive, X-linked, or maternal trait of inheritance. (scielo.br)
- Spasticity and weakness (spastic paresis) are the primary motor impairments after stroke and impose significant challenges for treatment and patient care. (frontiersin.org)
Autosomal recessive spastic paraplegia1
- 2007). A new locus for autosomal recessive spastic paraplegia (SPG32) on chromosome 14q12-q21 . (up.pt)
Known as hereditary spastic1
- Spastic paraplegia type 4 (also known as SPG4) is the most common of a group of genetic disorders known as hereditary spastic paraplegias. (medlineplus.gov)
Clinical6
- In terms of clinical manifestations, in addition to spastic paraplegia, three adrenomyeloneuropathy probands also had adrenocortical insufficiency, two Alexander disease probands developed urinary retention, one CTX proband developed cataracts and chronic diarrhea and the other presented with chronic diarrhea and mild tendon xanthomatosis. (dovepress.com)
- Several reports have shown that various late-onset leukodystrophies, such as X-linked adrenoleukodystrophy (ALD) and Krabbe disease (KD), may present as spastic paraplegia (SP) without leukodystrophy on neuroimaging and be easily misdiagnosed as hereditary spastic paraplegia (HSP) on clinical grounds. (dovepress.com)
- Hereditary spastic paraplegia: clinical features and pathogenetic mechanisms. (medscape.com)
- Hereditary Spastic Paraplegia: Beyond Clinical Phenotypes toward a Unified Pattern of Central Nervous System Damage. (medscape.com)
- Clinical features of hereditary spastic paraplegia due to spastin mutation. (medlineplus.gov)
- Spastic paraplegia 11 (SPG11) should be suspected in individuals with the following clinical and imaging findings. (nih.gov)
Spastin4
- Spastin, a new AAA protein, is altered in the most frequent form of autosomal dominant spastic paraplegia. (medscape.com)
- Fink JK, Rainier S. Hereditary spastic paraplegia: spastin phenotype and function. (medscape.com)
- Roll-Mecak A, Vale RD. Structural basis of microtubule severing by the hereditary spastic paraplegia protein spastin. (medlineplus.gov)
- Mutations in the spastin gene (SPAST) are associated with type 4 of HEREDITARY SPASTIC PARAPLEGIA. (bvsalud.org)
Mental retardation2
- She has a spastic gait disturbance, mental retardation, and extrapyramidal symptoms. (medscape.com)
- SENDA is a recently established subtype of neurode-generation with brain iron accumulation 14 that begins with early-onset spastic paraplegia and mental retardation, which remain static until adulthood. (nature.com)
Forms of spastic1
- Strümpell first described hereditary forms of spastic paraplegia (see the image below) in 1883, with Lorrain later providing more extensive detail. (medscape.com)
Mutations4
- SPG11 mutations are common in familial cases of complicated hereditary spastic paraplegia. (medscape.com)
- Mutations in the SPAST gene cause spastic paraplegia type 4. (medlineplus.gov)
- however, only the 2 subtypes involving mutations of SPG11 and SPG15 are associated with Kjellin's syndrome ( 1 1 Finsterer J, Loscher W, Quasthoff S, Wanschitz J, Auer-Grumbach M, Stevanin G. Hereditary spastic paraplegias with autosomal dominant, recessive, X-linked, or maternal trait of inheritance. (scielo.br)
- 2009). Novel SPG3A and SPG4 mutations in dominant spastic paraplegia families . (up.pt)
SPG43
- demonstrate through studies on induced pluripotent stem cell-derived cortical neurons that miR-33a is a potential therapeutic target for the treatment of SPG4-related hereditary spastic paraplegia. (portlandpress.com)
- Silver syndrome variant of hereditary spastic paraplegia: A locus to 4p and allelism with SPG4. (medscape.com)
- Rattay TW, Boldt A, Volker M, Wiethoff S, Hengel H, Schule R, Schols L. Non-motor symptoms are relevant and possibly treatable in hereditary spastic paraplegia type 4 (SPG4). (medlineplus.gov)
Optic Atrophy1
- Optic Atrophy (OA) is the most prevalent inherited optic neuropathy besides Leber's hereditary optic neuropathy (LHON). (preventiongenetics.com)
Diagnosis3
- Failure to rule out reversible forms of spinal cord lesions (mechanical cord compression or spinal cord tumor) when considering a diagnosis of hereditary spastic paraplegia (HSP) invites problems. (medscape.com)
- The Igenomix Hereditary Spastic Paraplegia Precision Panel can serve as a n accurate and directed diagnostic tool as well as a differential diagnosis of muscle weakness ultimately leading to a better management and prognosis of the disease. (igenomix.it)
- Diagnosis of hereditary spastic paraplegia is by exclusion of other causes and sometimes (eg, if the cause is unclear) by genetic testing. (msdmanuals.com)
Clinically and genetically1
- Hereditary spastic paraplegias (HSP) are clinically and genetically heterogenous monogenic disorders. (cegat.com)
SPAST1
- Las mutaciones en el gen de la espastina (SPAST) se asocian con el tipo 4 de la PARAPLEJIA ESPÁSTICA HEREDITARIA. (bvsalud.org)
Phenotypes1
- Tesson C, Koht J, Stevanin G. Delving into the complexity of hereditary spastic paraplegias: how unexpected phenotypes and inheritance modes are revolutionizing their nosology. (medscape.com)
Disorders5
- Hereditary spastic paraplegia (HSP) is a group of degenerative genetic disorders involving the spinal cord which are characterized by stiffness and progressive weakness of the affected person's legs. (disabled-world.com)
- Hereditary cerebellar ataxias (HCA) and hereditary spastic paraplegias (HSP) are two groups of neurodegenerative disorders that usually present with progressive gait impairment, often leading to permanent disability. (nih.gov)
- 128 patients (58 women, 70 men) from 109 families were recruited by specialised HSP outpatient clinics in Bochum, Kiel, and Tübingen, Germany, in the context of the German Network of Hereditary Movement Disorders (GeNeMove). (biomedcentral.com)
- Hereditary spastic paraplegia is a group of rare hereditary disorders characterized by progressive, spinal, nonsegmental spastic leg paresis, sometimes with intellectual disability, seizures, and other extraspinal deficits. (msdmanuals.com)
- His lab's research is primarily focused on studying several neurodegenerative disorders, including Tauopathies (such as Alzheimer's Disease and Frontotemporal Dementia) and Hereditary Spastic Paraplegia (HSP). (drexel.edu)
Genes1
- 2017). Massive sequencing of 70 genes reveals a myriad of missing genes or mechanisms to be uncovered in hereditary spastic paraplegias . (up.pt)
Gait disturbance1
- If symptoms begin during the teenage years or later, then spastic gait disturbance usually progresses over many years. (wikipedia.org)
Cerebral palsy1
- HSP is not a form of cerebral palsy even though it physically may appear and behave much the same as spastic diplegia. (wikipedia.org)
Symptoms4
- There is currently no treatment for hereditary spastic paraplegia (HSP), a set of genetic illnesses whose symptoms include muscle weakness and stiffness, and in some cases cognitive impairments. (news-medical.net)
- Patients with late-onset spastic paraplegia should be screened for underlying leukodystrophies, irrespective of the presence of additional complicating symptoms and neuroimaging abnormalities. (dovepress.com)
- Symptoms and signs of hereditary spastic paraplegia include spastic leg paresis, with progressive gait difficulty, hyperreflexia, clonus, and extensor plantar responses. (msdmanuals.com)
- researchers believe this contributes to the major signs and symptoms of spastic paraplegia type 4. (medlineplus.gov)
Prevalence1
- The prevalence of spastic paraplegia type 4 is estimated to be 2 to 6 in 100,000 people worldwide. (medlineplus.gov)
Cerebellar1
- The Cerebellar Ataxia & Hereditary Spastic Paraplegias Disease Knowledge Page provides reference information on care of cerebellar ataxia and hereditary spastic paraplegias. (ern-rnd.eu)
Inherited diseases1
- Hereditary spastic paraplegia (HSP) is a group of inherited diseases whose main feature is a progressive gait disorder. (wikipedia.org)
Diplegia2
Weakness1
- Hereditary spastic paraplegia (HSP) a degenerative genetic disorder with stiffness and weakness of leg and hip muscles gait difficulties and issues with walking. (disabled-world.com)
Neurological1
- Scientists at The Scripps Research Institute (TSRI) have discovered that a gene mutation linked to hereditary spastic paraplegia, a disabling neurological disorder, interferes with the normal breakdown of triglyceride fat molecules in the brain. (news-medical.net)
Patients6
- The objective of this study was to investigate the frequency of late-onset leukodystrophies in patients with spastic paraplegia. (dovepress.com)
- We performed genetic analysis using a custom-designed gene panel for leukodystrophies in 112 hereditary spastic paraplegia-like patients. (dovepress.com)
- Pattern visual evoked responses were studied in 13 patients from nine families with dominant herditary spastic paraplegia and in seven sporadic cases. (bmj.com)
- Hereditary spastic paraplegia: Clinicogenetic lessons from 608 patients. (medscape.com)
- Phenotype-genotype studies found that 20% of DOA patients develop a more severe phenotype called "DOA plus" (DOA+), which is characterized by extraocular multi-systemic features, including neurosensory hearing loss, or less commonly chronic progressive external ophthalmoplegia, myopathy, peripheral neuropathy, multiple sclerosis-like illness, spastic paraplegia or cataracts (Yu-Wai-Man et al. (preventiongenetics.com)
- The patients presented with pure spastic paraplegia with age of onset between 9 and 46 years. (cegat.com)
Dominant3
- Genetic loci for autosomal dominant pure hereditary spastic paraplegia (ADPHSP) have been mapped to chromosomes 2p, 8q, 12q, 14q, and 15q. (nih.gov)
- A novel heterozygous variant in ERLIN2 causes autosomal dominant pure hereditary spastic paraplegia. (cegat.com)
- 2013). Autosomal dominant spastic paraplegias: A review of 89 families resulting from a Portuguese survey . (up.pt)
Spinal1
- Multiple sclerosis, B12 deficiency, human T-cell lymphotrophic virus-1 infection, structural inflammatory lesions of the spinal cord, motor neuron disease, and hereditary spastic paraplegia have been excluded. (cdc.gov)
Genetic disorder1
- Roberts has a genetic disorder called hereditary spastic paraplegia, or HSP. (wate.com)
Mechanisms1
- We seek motivated applicants for a pre-doctoral / post-doctoral fellowship aimed at investigating molecular mechanisms of rare genetic forms of hereditary spastic paraplegia. (academicgates.com)
Type3
- There is a rare form of infantile-onset ascending hereditary spastic paralysis (IAHSP) that is considered by some in the field of medical research to be a rare type of hereditary spastic paraplegia. (disabled-world.com)
- Spastic paraplegia type 4 is usually a pure hereditary spastic paraplegia, although a few complex cases have been reported. (medlineplus.gov)
- Spastic paraplegia type 4 generally affects nerve and muscle function in the lower half of the body only. (medlineplus.gov)
Mutation1
- Hereditary spastic paraplegia caused by the novel mutation 1047insC in the SPG7 gene. (medscape.com)
Macular1
- Current faculty collaboration projects examine different aspects of breast and prostate cancer, age-related macular degeneration, hepatitis, respiratory electron flow, and hereditary spastic paraplegia. (rochester.edu)
Pure2
- Reid E. Pure hereditary spastic paraplegia. (medscape.com)
- Hereditary spastic paraplegias are divided into two types: pure and complex. (medlineplus.gov)
Affects1
- Hereditary spastic paraplegia affects both sexes. (msdmanuals.com)
Alteration1
- 2013). Alteration of ganglioside biosynthesis responsible for complex hereditary spastic paraplegia . (up.pt)