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*  COMPARATIVE STUDIES IN ROUS SARCOMA WITH VIRUS, TUMOR CELLS AND CHICK EMBRYO CELLS TRANSFORMED IN VITRO BY VIRUS | JEM
However, examination of the sex chromatin of cells at the periphery of the tumor shows presence of recipient cells though the ... retain the sex chromatin patterns of the donor cells when such cells are injected into a recipient of the opposite sex. ... Injection of RSV induces tumors of the sex of the recipient as also does the injection of transformed cells rendered incapable ... When such tumors induced by transformed cells are serially transferred in recipients of the opposite sex, they gradually ...
http://jem.rupress.org/content/116/3/329
*  Intragenomic conflict in populations infected by Parthenogenesis Inducing Wolbachia ends with irreversible loss of sexual...
... sex ratio chromosome in the parasitic wasp Trichogramma kaykai condenses the paternal chromosomes into a dense chromatin mass. ... Because of the increasingly female-biased sex ratio in the population during a spreading PI-Wolbachia infection, sex allocation ... These nucleo-cytoplasmic conflicts can have dramatic consequences on sex-allocation and sex-determination systems [1]. One of ... Hoekstra RF: The Evolution of Sexes. Experientia Supplementum (Basel), Vol 55 The Evolution of Sex and Its Consequences 403p ...
https://bmcevolbiol.biomedcentral.com/articles/10.1186/1471-2148-10-229
*  Changes in Incidence of Sex Chromatin in Subcultured Cells | Science
Sex chromatin counts of subcultured cells of both female human mammary tumor and female rabbit kidney show a considerable drop ... Changes in Incidence of Sex Chromatin in Subcultured Cells Message Subject. (Your Name) has forwarded a page to you from ... Cultures in which sex chromatin persists also retain the viral insensitivity of their source material. ...
http://science.sciencemag.org/content/133/3445/43
*  Sex Chromatin - Semantic Scholar
Each X CHROMOSOME, in excess of one, forms sex chromatin (Barr body) in the mammalian nucleus. (from King & Stansfield, A ... a condensed mass of chromatin representing an inactivated X chromosome. ... Sex Chromatin. Known as: chromatin sex, Chromatins, Sex, Barr bodies (More). In the interphase nucleus, a condensed mass of ... Moth sex chromatin probed by comparative genomic hybridization (CGH).. *Ken Sahara, Franttisek Marec, Ulrike Eickhoff, Walther ...
https://www.semanticscholar.org/topic/Sex-Chromatin/273923
*  Sex chromatins Synonyms, Sex chromatins Antonyms | Thesaurus.com
Synonyms for sex chromatins at Thesaurus.com with free online thesaurus, antonyms, and definitions. Find descriptive ... sex chromatins. .css-c3577y{font-size:14px;color:#a19f9c;padding-bottom:18px;display:block;}. noun. chromosome determining sex ... sex chromatins. .css-16tby2r{color:#3c7bbe;font-size:13px;font-weight:600;position:relative;bottom:5px;}. see definition of sex ...
https://www.thesaurus.com/browse/sex%20chromatins
*  Sex chromatin in mental retardation | Springer for Research & Development
The incidence of chromatin positivity among male mental defectives was found to be 4.2 per... ... Barr, M. L. and Carr, D. H. (1960). Sex chromatin, sex chromosomes and sex anomalies.Canad. med. Ass. J. 83, 979.PubMedGoogle ... Observations on the female sex chromatin in human epidermis and on the value of skin biopsy in determining sex.J. Path. Bact. ... Gustavson, K. H., and Akeeson, H. A. (1961). Mental deficiency and aberrant sex chromatin.Ibid. 2, 724.CrossRefGoogle Scholar ...
https://rd.springer.com/article/10.1007/BF02755407
*  The Sex Chromatin, Or The "Barr Body" | Canadians for Health Research | Les Canadiens pour la recherche medicale
The research during which the sex chromatin was discovered belongs to the category of research known as curiosity-driven ... It was therefore named the sex chromatin because of the sex difference and this discovery was the beginning of the new science ... The research during which the sex chromatin was discovered belongs to the category of research known as curiosity-driven ... The research during which the sex chromatin was discovered belongs to the category of research known as curiosity-driven ...
https://chrcrm.org/en/salute-excellence/sex-chromatin-or-barr-body
*  Moth sex chromatin probed by comparative genomic hybridization (CGH) : HUSCAP
Moth sex chromatin probed by comparative genomic hybridization (CGH). フルテキスト Genome46(2).pdf. 1.16 MB. PDF. 見る/開く. ... Moth sex chromatin probed by comparative genomic hybridization (CGH). 著者: Sahara, Ken 著作を一覧する. Marec, František 著作を一覧する. ... Our results show that CGH can be applied to obtain a first estimate of the sequence composition of sex chromosomes in species ... of differently labeled genomic DNA from females and males highlighted the W chromosomes in mitotic plates and the W chromatin ...
https://eprints.lib.hokudai.ac.jp/dspace/handle/2115/891
*  The impact of testicular and accessory sex gland function ion sperm chromatin integrity as assessed by the sperm chromatin...
The impact of testicular and accessory sex gland function ion sperm chromatin integrity as assessed by the sperm chromatin ... accessory sex glands, SCSA, sperm chromatin, zine, testosterone. in Human Reproduction. volume. 17. issue. 12. pages. 3162 - ... The impact of testicular and accessory sex gland function ion sperm chromatin integrity as assessed by the sperm chromatin ... BACKGROUND: The sperm chromatin structure assay (SCSA) provides an objective assessment of sperm chromatin integrity, which is ...
https://lup.lub.lu.se/search/publication/892161
*  Sex chromosome control of chromatin in the gametes - Bluma Lesch
The sex chromosomes of mammalian germ cells must match those of the surrounding soma in order for the germ cells to ... Sex chromosome control of chromatin in the gametes Lesch, Bluma Jessica Whitehead Institute for Biomedical Research, Cambridge ... Sex chromosome control of chromatin in the gametes. Lesch, Bluma Jessica / Whitehead Institute for Biomedical Research. $59,966 ... Sex chromosome control of chromatin in the gametes. Lesch, Bluma Jessica / Whitehead Institute for Biomedical Research. ...
http://grantome.com/grant/NIH/F32-HD075591-01A1
*  KAKEN - Research Projects | Analysis of chromatin structure and gene function of chicken sex chromosomes (KAKENHI-PROJECT...
Analysis of chromatin structure and gene function of chicken sex chromosomes. Research Project ... Publications] Shigeki Mizuno: 'Sex-specific DNA sequences in Galliformes and their application to the study of sex ... Chicken / Sex Chromosome / W Chromosome / Z Chromosome / Heterochromatin / Sex Chromosome-speicific Library / Genomic Library ... Constitution of chicken sex chromosomes is ZW for female and ZZ for male. About 2/3 of the W chromosome and a terminal region ...
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-05454068/
*  Ancestral chromatin configuration constrains chromatin evolution on differentiating sex chromosomes in Drosophila | Haldane's...
... dx.doi.org/10.1101/019786 Sex chromosomes evolve distinctive types of chromatin from a pair of ancestral autosomes that are ... In Drosophila, the dosage-compensated X becomes enriched for hyperactive chromatin in males (mediated by H4K16ac), while the Y ... Ancestral chromatin configuration constrains chromatin evolution on differentiating sex chromosomes in Drosophila Qi Zhou, ... Ancestral chromatin configuration constrains chromatin evolution on differentiating sex chromosomes in Drosophila. Posted on ...
https://haldanessieve.org/2015/05/26/ancestral-chromatin-configuration-constrains-chromatin-evolution-on-differentiating-sex-chromosomes-in-drosophila/
*  Chromatin structural changes around satellite repeats on the female sex chromosome in Schistosoma mansoni and their possible...
... repeat-induced chromatin structure changes could indeed be the initial event in sex chromosome emergence. ... Our study provides for the first time evidence for the hypothesis that, at least in organisms with a ZW type of sex chromosomes ... Transcription and chromatin status of female-specific repeats are stage-specific: for those repeats that are transcribed, ... mansoni sex chromosomes. We show that 70 to 90% of S. mansoni W and Z are pseudoautosomal. No female-specific gene could be ...
https://genomebiology.biomedcentral.com/articles/10.1186/gb-2012-13-2-r14
*  H2AFY - Core histone macro-H2A.1 - Homo sapiens (Human) - H2AFY gene & protein
... which induces a hypoacetylated state of chromatin (PubMed:16428466, PubMed:16107708). ... Nucleosomes wrap and compact DNA into chromatin, limiting DNA accessibility to the cellular machineries which require DNA as a ... sex chromatin Source: BHF-UCL ,p>Traceable Author Statement,/p> ,p>Used for information from review articles where the original ... chromatin DNA binding Source: UniProtKB ,p>Inferred from Direct Assay,/p> ,p>Used to indicate a direct assay for the function, ...
https://www.uniprot.org/uniprot/O75367
*  Corpus ciliare | definition of corpus ciliare by Medical dictionary
Barr body sex chromatin.. basal body a modified centriole that occurs at the base of a flagellum or cilium. ... Howell's b's (Howell-Jolly b's) smooth, round remnants of nuclear chromatin seen in erythrocytes in megaloblastic and hemolytic ...
https://medical-dictionary.thefreedictionary.com/corpus+ciliare
*  Geniculate b's (medial) | definition of geniculate b's (medial) by Medical dictionary
Barr body sex chromatin.. basal body a modified centriole that occurs at the base of a flagellum or cilium. ... Howell's b's (Howell-Jolly b's) smooth, round remnants of nuclear chromatin seen in erythrocytes in megaloblastic and hemolytic ... secondary sex characteristic. Endocrinology The constellation of changes in hair distribution, body configuration, and genital ... sex, weight, body fat, and physical condition. No matter how much alcohol is consumed or what blood alcohol concentration level ...
http://medical-dictionary.thefreedictionary.com/geniculate+b
*  OB/Gyn Vocab Quiz - By roberson16
Sex chromatin masses on the nuclear membrane. The number of these is one fewer than the number of X chromosomes in that cell.. ... A person who exhibits characteristics of both sexes. A true hermaphrodite is characterized by the presence of both ovarian and ... An individual's understanding and feeling of the activity and behavior appropriate to the male or female sex.. ... A symptom complex caused by hypersecretion of glucocorticoids, mineralocorticoids, and sex hormones of the adrenal cortex.. ...
https://www.sporcle.com/games/roberson16/obgyn-vocab
*  Bar body | definition of Bar body by Medical dictionary
Synonym(s): Barr body; sex chromatin. Barr body. a small mass of densely staining chromatin seen during interphase of female ... a sex CHROMATIN particle found in the interphase nucleus of buccal epithelial cells in some female mammals and probably derived ... Barr body - Synonym(s): Barr chromatin body. Barr chromatin body - a small condensed mass of the inactivated X-chromosome ... Sex chromatin in nuclei from human male and female buccal epithelial cells. ...
http://medical-dictionary.thefreedictionary.com/Bar+body
*  Techniques to Determine Clonality in Hematolymphoid Malignancies | SpringerLink
Sex chromatin and gene action in the mammalian X-chromosome. Am J Hum Genet. 1962;14:135-148.PubMedGoogle Scholar ...
https://link.springer.com/chapter/10.1007/978-1-4419-5698-9_8
*  Susumo Ohno | Biographical Memoirs: V.81 | The National Academies Press
Formation of the sex chromatin by a single X-chromosome in liver cells of Rattus norvegicus. Exp. Cell Res. 18:415-18. ... 1967 Sex Chromosomes and Sex-Linked Genes. Heidelberg: Springer-Verlag.. 1970 Evolution by Gene Duplication. Berlin: Springer ... These were Sex Chromosomes and Sex-Linked Genes published in 1967, Evolution by Gene Duplication published in 1970, and Major ... The single-X nature of sex chromatin in man. Lancet 1:78-79. ... Sex-linkage of G-6-PD in the horse and donkey. Fed. Proc. 24: ...
https://www.nap.edu/read/10470/chapter/14
*  Medical Laboratory Science
Sex chromatin determination. * PATH 304 - Normal Human Histology An advanced lecture and laboratory course in the microscopic ...
http://you.ubc.ca/ubc_programs/medical-laboratory-science/
*  Survival of Donor-Derived Cells in Human Corneal Transplants | IOVS | ARVO Journals
Sex chromatin as a biologic cell marker in the study of the fate of corneal transplants. Am J Ophthalmol. 1960;49:513-515. [ ... Sex-chromatin-charakter der implantierten scheibe. Albrecht von Graefes Arch Ophthalmol. 1963;166:180-187. [CrossRef] [PubMed] ... The fate of the endothelial cells of the graft as determined by sex chromatin studies. Am J Ophthalmol. 1961;52:91-95. [ ... Analysis of sex-mismatched human corneal transplants by fluorescence in situ hybridization of the sex chromosomes. Exp Eye Res ...
https://iovs.arvojournals.org/article.aspx?articleid=2126551
*  Mary F. Lyon - Wikipedia
Lyon, M. F. (1962). "Sex chromatin and gene action in the mammalian X-chromosome". American Journal of Human Genetics. 14: 135- ... In 1997 she also received the Amory Prize, for genetic discoveries relating to mammalian sex chromosomes. In 2004 she was ...
https://en.wikipedia.org/wiki/Mary_F._Lyon
*  Dysmorphophobia | definition of dysmorphophobia by Medical dictionary
Barr body sex chromatin.. basal body a modified centriole that occurs at the base of a flagellum or cilium. ... Howell's b's (Howell-Jolly b's) smooth, round remnants of nuclear chromatin seen in erythrocytes in megaloblastic and hemolytic ...
http://medical-dictionary.thefreedictionary.com/dysmorphophobia

*  Mary F. Lyon
Lyon, M. F. (1962). "Sex chromatin and gene action in the mammalian X-chromosome". American Journal of Human Genetics. 14: 135- ... In 1997 she also received the Amory Prize, for genetic discoveries relating to mammalian sex chromosomes. In 2004 she was ...
*  Nuclear sexing
A minimum of 30 percent of sex chromatin indicates genetic female sex. Barr, M. L.; Bertram, E. G. (1949-04-30). "A ... Nuclear sexing is a technique for genetic sex determination in those species where XX chromosome pair is present. Nuclear ... sexing can be done by identifying Barr body, a drumstick like appendage located in the rim of the nucleus in somatic cells. ...
*  Dosage compensation
Cock A.G. (1964). "Dosage compensation and sex-chromatin in non-mammals". Genet Res Camb. 5: 354-365. doi:10.1017/ ... This system of sex determination is unique, because there is no male specific chromosome, as is the case in XX/XY sex ... Across species, different sexes are often characterized by different types and numbers of sex chromosomes. In order to account ... Ohno, Susumu (1959). "Sex chromosomes and sex-linked genes". Teratology. 4: 111. doi:10.1002/tera.1420040116. Lyon, M.F. (1961 ...
*  1985 Summer Universiade
The sex chromatin test was used at these games to decide on participants' gender; Spanish hurdler Maria José Martínez-Patiño ... "The Humiliating Practice of Sex-Testing Female Athletes". New York Times. Ljungqvist, A. (2008-04-15). "Gender Verification". ...
*  Susumu Ohno
ISBN 0-04-575015-7. Ohno S, Kaplan WD, Kinosita R (1959). "Formation of the sex chromatin by a single X-chromosome in liver ... Ohno S (1967). Sex Chromosomes and Sex-Linked Genes. Berlin, New York: Springer-Verlag Wycoff, Mick (2008). "Art as Science ...
*  X-inactivation
CS1 maint: Multiple names: authors list (link) Ohno S, Kaplan WD, Kinosita R (1959). "Formation of the sex chromatin by a ... unlike the majority of genes along the sex chromosomes. Since individuals of either sex will receive two copies of every gene ... These regions are termed pseudoautosomal regions, as individuals of either sex will receive two copies of every gene in these ... Examining normal tissues and tumors from females heterozygous for isoenzymes of the sex-linked G6PD gene demonstrated that ...
*  Biomarker
Basu, P. K.; Miller, I.; Ormsby, H. L. (1960-03-01). "Sex chromatin as a biologic cell marker in the study of the fate of ...
*  Maria José Martínez-Patiño
The sex chromatin test was, at the time, the first step in the gender verification process, and not intended to provide a ... she failed the sex chromatin test in 1985, and thus was ruled ineligible to participate in women's athletics. The test was ... Wiesemann, Claudia (2011). "Is there a right not to know one's sex? The ethics of 'gender verification' in women's sports ... Ruth Padawer (June 28, 2016). "The Humiliating Practice of Sex-Testing Female Athletes". New York Times. Bardin, Jon (30 July ...
*  Harry Klinefelter
Eighty percent of these patients have positive sex chromatin, and their karyotypes may vary widely, and with many mosaics. The ... Although these patients have positive female sex chromatin, they are phenotypic males and should never be considered otherwise ... or were chromatin positive. A few years later, Jacobs and Strong found that these chromatin-positive patients had 47 ... Anaphase lag might result in a gamete losing a sex chromosome; a chromosome lags and is not incorporated in the new cell in the ...
*  List of MeSH codes (A11)
... sex chromosomes MeSH A11.284.187.865.800 - sex chromatin MeSH A11.284.187.865.982 - x chromosome MeSH A11.284.187.865.982.500 ... sex chromatin MeSH A11.284.430.106.279.345.190.160.180.625 - nucleosomes MeSH A11.284.430.106.279.345.190.160.650 - nucleolus ... sex MeSH A11.284.180.700 - pseudopodia MeSH A11.284.183.200 - cell wall skeleton MeSH A11.284.187.167 - chromosomes, archaeal ... chromatin MeSH A11.284.430.106.279.345.190.160.180.270 - euchromatin MeSH A11.284.430.106.279.345.190.160.180.383 - ...
*  List of MeSH codes (G14)
... sex chromatin MeSH G14.162.865.982 --- x chromosome MeSH G14.162.865.982.500 --- chromosomes, human, x MeSH G14.162.865.983 ... sex chromatin MeSH G14.160.180.625 --- nucleosomes MeSH G14.162.178.170 --- chromosomes, artificial, bacterial MeSH G14.162. ...
*  Klinefelter syndrome
... determination of the sex chromatin, and prenatally via chorionic villus sampling or amniocentesis. A 2002 literature review of ... Nondisjunction will occur when sister chromatids on the sex chromosome, in this case an X and an X, fail to separate. (meiosis ... MACLEAN N, HARNDEN DG, COURT BROWN WM; Harnden; Court Brown (Aug 1961). "Abnormalities of sex chromosome constitution in ... Linden MG, Bender BG, Robinson A (1995). "Sex chromosome tetrasomy and pentasomy". Pediatrics. 96 (4 Pt 1): 672-682. PMID ...
*  XYY syndrome
... sex chromatin bodies was not developed until 1970, a decade after the first reported sex chromosome aneuploidy. The first ... Screening for those X chromosome aneuploidies was possible by noting the presence or absence of "female" sex chromatin bodies ( ... sex chromatin bodies in the nuclei of interphase cells in buccal smears treated with quinacrine dihydrochloride, which could be ... In the wake of the establishment of the normal number of human chromosomes, 47,XYY was the last of the common sex chromosome ...
*  ASXL1
1998). "The Additional sex combs gene of Drosophila encodes a chromatin protein that binds to shared and unique Polycomb group ... In Drosophila, the Additional sex combs (Asx) gene encodes a chromatin-binding protein required for normal determination of ... "A human homolog of Additional sex combs, ADDITIONAL SEX COMBS-LIKE 1, maps to chromosome 20q11". Gene. 306: 115-26. doi:10.1016 ... The protein is thought to disrupt chromatin in localized areas, enhancing transcription of certain genes while repressing the ...
*  Ridge (biology)
The authors reasoned this was due to the low rate of chromosomal rearrangements of sex chromosomes. Open chromatin regions are ... When the chromatin of one gene is opened, the chromatin of the adjacent genes is also until this modification meets a boundary ... Chromatin consists of the DNA strand and histones that are attached to the DNA. Regions were chromatin is very tightly packed ... Chromatin which consists of functional genes is often an open structure were the DNA is accessible. However, most of the genes ...
*  HORMAD1
... a process believed to form the basis of meiotic silencing of unsynapsed chromatin (MSUC) and meiotic prophase quality control ... in both sexes (By similarity) GRCh38: Ensembl release 89: ENSG00000143452 - Ensembl, May 2017 GRCm38: Ensembl release 89: ...
*  M33 (gene)
1998) indicates that homozygous M33-mutant mice represent the first case in which male-to-female gonadal sex reversal results ... Polycomb genes in Drosophila mediate changes in higher-order chromatin structure to maintain the repressed state of ... Ono, Makoto; Harley, Vincent R. (2013-02-01). "Disorders of sex development: new genes, new concepts". Nature Reviews. ... "Male-to-female sex reversal in M33 mutant mice". Nature. 393 (6686): 688-692. doi:10.1038/31482. ISSN 0028-0836. PMID 9641679 ...
*  Testis-determining factor
... and identifying the genes that transcription factors act on using chromatin immunoprecipitation. Y chromosome Sex-determination ... Monotremes lack SRY and some of their sex chromosomes share homology with bird sex chromosomes. SRY is a quickly evolving gene ... GeneReviews/NCBI/NIH/UW entry on 46,XX Testicular Disorder of Sex Development OMIM entries on 46,XX Testicular Disorder of Sex ... Müller J, Schwartz M, Skakkebaek NE (July 1992). "Analysis of the sex-determining region of the Y chromosome (SRY) in sex ...
*  Paul Schedl
On the genomic level, his lab has uncovered the mechanisms of chromatin regulation by the Polycomb and trithorax group genes. ... he made discoveries in the regulation of alternative splicing of the sex determination gene, Sxl. At the level of translational ...
*  Plasmodium carmelinoi
The sex ratio was 1 male to 2.2 females. This parasite is found in Brazil. Not known. P. carmelinoi infects the teiid lizard ( ... micrometres and stain an over-all pink colour due to the dispersed nuclear chromatin. Macrogametocytes measure 5.7 (4.4 - 5.9) ...
*  Meiotic recombination checkpoint
Meiotic sex chromosome inactivation only happens in male, which may partially be the reason why only Spo11 mutant spermatocytes ... "A High Incidence of Meiotic Silencing of Unsynapsed Chromatin Is Not Associated with Substantial Pachytene Loss in Heterozygous ... Some other studies also drew sex body formation into attention, and the signaling could be either structure based or ... Under this cascade, failure to synapse will maintain the gene expression from sex chromosomes and some products may inhibit ...
*  BRDT
Homozygous mutant males were sub-fertile and both sexes had a decreased number of lumbar and sacral vertebrae. BET inhibitors ... 2003). "Acetylation-Dependent Chromatin Reorganization by BRDT, a Testis-Specific Bromodomain-Containing Protein". Mol. Cell. ... such as JQ1 block the region of BRDT responsible for chromatin binding, and cause a reversible reduction of sperm production, ... could be explained by considering Brdt's functions as a driver of testis-specific gene expression and post-meiotic chromatin ...
*  Genetics
2000). "Sex chromosomes and sex-linked inheritance". An Introduction to Genetic Analysis (7th ed.). New York: W. H. Freeman. ... forming a material called chromatin; in eukaryotes, chromatin is usually composed of nucleosomes, segments of DNA wound around ... In 1911, Thomas Hunt Morgan argued that genes are on chromosomes, based on observations of a sex-linked white eye mutation in ... Many species have so-called sex chromosomes that determine the gender of each organism. In humans and many other animals, the Y ...
*  Dextroamphetamine
Blum K, Werner T, Carnes S, Carnes P, Bowirrat A, Giordano J, Oscar-Berman M, Gold M (March 2012). "Sex, drugs, and rock 'n' ... Renthal W, Nestler EJ (September 2009). "Chromatin regulation in drug addiction and depression". Dialogues Clin. Neurosci. 11 ( ... These sex addictions are associated with a dopamine dysregulation syndrome which occurs in some patients taking dopaminergic ... Zhou Y, Zhao M, Zhou C, Li R (July 2015). "Sex differences in drug addiction and response to exercise intervention: From human ...
*  Prophase
Sex (X and Y) chromosomes do not fully synapse because only a small region of the chromosomes are homologous. The nucleolus ... Chromatin has condensed enough that chromosomes can now be resolved in microscopy. Structures called recombination nodules form ... Each chromosome is in a haploid state and consists of two sister chromatids; however, the chromatin of the sister chromatids is ... Prophase I occurs at different speeds dependent on species and sex. Many species arrest meiosis in diplotene of prophase I ...
*  Transgenerational stress inheritance
Chromatin remodeling in rodent offspring and altered gene expression within the limbic brain regions that may contribute to ... Hodes GE, Walker DM, Labonté B, Nestler EJ, Russo SJ (January 2017). "Understanding the epigenetic basis of sex differences in ...

(1/76) Origin of DNA damage in ejaculated human spermatozoa.

The molecular basis of many forms of male infertility is poorly defined. One area of research that has been studied intensely is the integrity of the DNA in the nucleus of mature ejaculated spermatozoa. It has been shown that, in men with abnormal sperm parameters, the DNA is more likely to possess strand breaks. However, how and why this DNA damage originates in certain males and how it may influence the genetic project of a mature spermatozoon is unknown. Two theories have been proposed to describe the origin of this DNA damage in mature spermatozoa. The first arises from studies performed in animal models and is linked to the unique manner in which mammalian sperm chromatin is packaged, while the second attributes the nuclear DNA damage in mature spermatozoa to apoptosis. One of the factors implicated in sperm apoptosis is the cell surface protein, Fas. In this review, we discuss the possible origins of DNA damage in ejaculated human spermatozoa, how these spermatozoa arrive in the ejaculate of some men, and what consequences they may have if they succeed in their genetic project.  (+info)

(2/76) Histone macroH2A1.2 relocates to the inactive X chromosome after initiation and propagation of X-inactivation.

The histone macroH2A1.2 has been implicated in X chromosome inactivation on the basis of its accumulation on the inactive X chromosome (Xi) of adult female mammals. We have established the timing of macroH2A1.2 association with the Xi relative to the onset of X-inactivation in differentiating murine embryonic stem (ES) cells using immuno-RNA fluorescence in situ hybridization (FISH). Before X-inactivation we observe a single macroH2A1.2-dense region in both undifferentiated XX and XY ES cells that does not colocalize with X inactive specific transcript (Xist) RNA, and thus appears not to associate with the X chromosome(s). This pattern persists through early stages of differentiation, up to day 7. Then the frequency of XY cells containing a macroH2A1.2-rich domain declines. In contrast, in XX cells there is a striking relocalization of macroH2A1.2 to the Xi. Relocalization occurs in a highly synchronized wave over a 2-d period, indicating a precisely regulated association. The timing of macroH2A1.2 accumulation on the Xi suggests it is not necessary for the initiation or propagation of random X-inactivation.  (+info)

(3/76) Higher concentrations of histone macroH2A in the Barr body are correlated with higher nucleosome density.

Histone macroH2A, which is a subtype of histone H2A, possesses a histone H2A-like portion fused to a relatively long non-histone portion. MacroH2A has been shown to associate preferentially with the inactive X chromosome [1]. To investigate the specificity of this association, the nuclear distribution of macroH2A was compared with that of regular core histones. In normal human female fibroblasts, all anti-histone antibodies that were tested (including anti-macroH2A antibody) preferentially labeled the inactive X chromosome. Moreover, when expressed as green fluorescent protein (GFP) fusions, both histone H2A and macroH2A were concentrated in the Barr body. These data clearly show the presence of a higher density of nucleosomes in the inactive X chromosome. Accordingly, the specificity of the macroH2A association with the inactive X chromosome should be reconsidered. While investigating the role of macroH2A, we found that the proximity of the non-histone region of macroH2A to a promoter could lead to a specific repression of transcription, suggesting that the incorporation of macroH2A into chromatin might help to establish the stable pattern of gene expression in differentiated cells.  (+info)

(4/76) The JIL-1 tandem kinase mediates histone H3 phosphorylation and is required for maintenance of chromatin structure in Drosophila.

To analyze the function of the chromosomal kinase JIL-1, we generated an allelic series of hypomorphic and null mutations. JIL-1 is an essential kinase for viability, and reduced levels of JIL-1 kinase activity lead to a global change in chromatin structure. In JIL-1 hypomorphs, euchromatic regions of polytene chromosomes are severely reduced and the chromosome arms condensed. This is correlated with decreased levels of histone H3 Ser10 phosphorylation. These levels can be restored by a JIL-1 transgene placing JIL-1 directly in the pathway mediating histone H3 phosphorylation. We propose a model where JIL-1 kinase activity is required for maintaining the structure of the more open chromatin regions that facilitate gene transcription.  (+info)

(5/76) Identification of an autoimmune serum containing antibodies against the Barr body.

Transcriptional inactivation of one X chromosome in mammalian female somatic cells leads to condensation of the inactive X chromosome into the heterochromatic sex chromatin, or Barr body. Little is known about the molecular composition and structure of the Barr body or the mechanisms leading to its formation in female nuclei. Because human sera from patients with autoimmune diseases often contain antibodies against a variety of cellular components, we reasoned that some autoimmune sera may contain antibodies against proteins associated with the Barr body. Therefore, we screened autoimmune sera by immunofluorescence of human fibroblasts and identified one serum that immunostained a distinct nuclear structure with a size and nuclear localization consistent with the Barr body. The number of these structures was consistent with the number of Barr bodies expected in diploid female fibroblasts containing two to five X chromosomes. Immunostaining with the serum followed by fluorescence in situ hybridization with a probe against XIST RNA demonstrated that the major fluorescent signal from the autoantibody colocalized with XIST RNA. Further analysis of the serum showed that it stains human metaphase chromosomes and a nuclear structure consistent with the inactive X in female mouse fibroblasts. However, it does not exhibit localization to a Barr body-like structure in female mouse embryonic stem cells or in cells from female mouse E7.5 embryos. The lack of staining of the inactive X in cells from female E7.5 embryos suggests the antigen(s) may be involved in X inactivation at a stage subsequent to initiation of X inactivation. This demonstration of an autoantibody recognizing an antigen(s) associated with the Barr body presents a strategy for identifying molecular components of the Barr body and examining the molecular basis of X inactivation.  (+info)

(6/76) Micropenis associated with testicular agenesis.

This paper describes 2 male infants who were born with sever micropenis and in whom testicular tissue could not be identified at surgery. HCG stimulation in one infant was not followed by a rise in plasma testosterone. It was decided that both cases would be best raised as females, despite their male chromosomal sex.  (+info)

(7/76) A developmental study of girls with trisomy X.

Development of 11 girls (ages 2-10 years) with 47,XXX karyotype identified in a newborn survey is compared with eight girls having a mosaic sex chromatin pattern and with the normal siblings of each group. Delay in early motor development and speech, a mild intellectual deficit, and disturbance in interpersonal relationships occurred in one-third of the index cases, a higher frequency than in the comparison groups. two-thirds were considered normal and adequately adjusted. No consistent phenotype was found.  (+info)

(8/76) Human X-autosome translocations: differential inactivation of the X chromosome in a kindred with an X-9 translocation.

A kindred with an X-autosome translocation and differential inactivation of the X chromosome is described. The phenotypically normal mother has a reciprocal translocation [46,X,rcp(X;9) (q11;q32)] while the daughter's karyotype is unbalanced [46,X,--X,+der(9),rcp(X;9) (q11;q32)mat], indicating adjacent-two type of segregation in the mother. In the mother's cells the normal X is late replicating, while in the daughter's cells almost the entire der(9) is late replicating, indicating the presence of autosomal inactivation. The daughter's abnormal phenotype can be explained by her sex chromosomal complement and the absence of effective trisomy 9. At this stage there is no simple explanation to account for all types of inactivation patterns encountered in the 14 balanced and 15 unbalanced cases of X-autosome translocations reported to date. Selection of X inactivation is not an inherent characteristic of the X chromosome per se, and it is not dependent on the direction of chromosomal exchange, as was suggested previously. Correlation of the phenotypic and cytogenetic features of these patients suggests a pattern of X and autosomal inactivation consistent with the least amount of genotypic and phenotypic imbalance in most cases. The data are most consistent with random X inactivation followed by selection of the most viable cell line.  (+info)


  • retain
  • Chick embryo fibroblasts infected with Rous sarcoma virus in vitro are rendered malignant for such cells produce typical Rous sarcomas when injected into susceptible chicks since the tumors produced predominantly retain the sex chromatin patterns of the donor cells when such cells are injected into a recipient of the opposite sex. (rupress.org)
  • Cultures in which sex chromatin persists also retain the viral insensitivity of their source material. (sciencemag.org)
  • However
  • However, examination of the sex chromatin of cells at the periphery of the tumor shows presence of recipient cells though the bulk of the tumor is clearly of donor cell origin. (rupress.org)
  • The symbionts, with their maternal inheritance, benefit from inducing the production of exclusively daughters, however the optimal sex ratio for the nuclear genome is more male-biased. (biomedcentral.com)
  • cells
  • Injection of RSV induces tumors of the sex of the recipient as also does the injection of transformed cells rendered incapable of multiplication by x-rays. (rupress.org)
  • When such tumors induced by transformed cells are serially transferred in recipients of the opposite sex, they gradually convert to the sex of the recipient indicating that the tumors are not indefinitely transplantable. (rupress.org)
  • Sex chromatin counts of subcultured cells of both female human mammary tumor and female rabbit kidney show a considerable drop from an initial high level. (sciencemag.org)
  • female
  • Because of the increasingly female-biased sex ratio in the population during a spreading PI- Wolbachia infection, sex allocation alleles in the host that cause the production of more sons are rapidly selected. (biomedcentral.com)
  • Therefore, selection at the cytoplasmic level favors any manipulation of the sex ratio increasing female production. (biomedcentral.com)
  • gene
  • Levels of reproductive hormones, the length of the CAG repeat of the androgen receptor gene, sperm concentration, abstinence period and biochemical parameters of epididymal and accessory sex gland secretions were correlated to the SCSA parameters, DNA fragmentation index (DFI) and highly. (lu.se)
  • In Drosophila, the Additional sex combs (Asx) gene encodes a chromatin-binding protein required for normal determination of segment identity in the developing embryo. (wikipedia.org)
  • 1998) indicates that homozygous M33-mutant mice represent the first case in which male-to-female gonadal sex reversal results from a defect in a known recessive gene. (wikipedia.org)
  • Testis-determining factor (TDF), also known as sex-determining region Y (SRY) protein, is a DNA-binding protein (also known as gene-regulatory protein/transcription factor) encoded by the SRY gene that is responsible for the initiation of male sex determination in humans. (wikipedia.org)
  • mutations in this gene lead to a range of sex-related disorders with varying effects on an individual's phenotype and genotype. (wikipedia.org)
  • SRY is a quickly evolving gene and its regulation has been difficult to study because sex determination is not a highly conserved phenomenon within the animal kingdom. (wikipedia.org)
  • Deletion of the gene resulted in complete sex reversal. (wikipedia.org)
  • At the transcriptional and post-transcriptional level, he made discoveries in the regulation of alternative splicing of the sex determination gene, Sxl. (wikipedia.org)
  • differentiation
  • These two pairs of X-Y histone demethylase homologs target H3K4me3 and H3K27me3, two chromatin marks that play a central role in regulating the balance between pluripotency and differentiation. (grantome.com)
  • By setting up different chromatin states at important promoters in XX and XY germ cells, the X/Y-encoded demethylases may predispose these cells to respond differently to cues from XX or XY somatic tissue, thus enabling appropriate male or female gamete differentiation. (grantome.com)
  • Publications] Shigeki Mizuno: 'Sex-specific DNA sequences in Galliformes and their application to the study of sex differentiation' In : Manipulation of the Avian Genome (R.J.Etches and A.M.V.Gibbins, eds. (nii.ac.jp)
  • Abstract
  • article{7cc3097b-22b4-448a-9bce-4c18189ec61f, abstract = {BACKGROUND: The sperm chromatin structure assay (SCSA) provides an objective assessment of sperm chromatin integrity, which is essential for normal sperm function. (lu.se)
  • gamete
  • Fulfillment of each of these aims will enhance our current understanding of sex-specific gamete development, and improve clinical approaches to disorders of fertility and early embryonic development. (grantome.com)
  • autosomes
  • In this model, the emergence of a locus with female fertility and male sterility and another locus with male fertility and female sterility led to the establishment of a small sex-determining region on ordinary autosomes in hermaphrodite ancestors. (biomedcentral.com)
  • Transcription
  • Transcription and chromatin status of female-specific repeats are stage-specific: for those repeats that are transcribed, transcription is restricted to the larval stages lacking sexual dimorphism. (biomedcentral.com)
  • sperm
  • BACKGROUND: The sperm chromatin structure assay (SCSA) provides an objective assessment of sperm chromatin integrity, which is essential for normal sperm function. (lu.se)
  • CONCLUSIONS: Sex steroid production, spermatogenic function, abstinence time and seminal vesicle function appear to impact on sperm chromatin integrity and thereby on sperm fertilizing capacity. (lu.se)
  • Known
  • The research during which the sex chromatin was discovered belongs to the category of research known as curiosity-driven research, as opposed to clinical investigation. (chrcrm.org)
  • structure
  • Publications] Noriyuki Suka: 'W-heterochromatin of chicken;its unusual DNA components,late replication,and chromatin structure' Genetica. (nii.ac.jp)
  • its unusual DNA components, late replication, and chromatin structure' Genetica. (nii.ac.jp)
  • Primary
  • A survey of sex chromatin abnormalities among 4514 mental defectives, Primary microorchisism as seen in mentally handicapped children. (springer.com)
  • Its expression causes the development of primary sex cords, which later develop into seminiferous tubules. (wikipedia.org)
  • human
  • Sex chromatin counts of subcultured cells of both female human mammary tumor and female rabbit kidney show a considerable drop from an initial high level. (sciencemag.org)
  • current
  • In "Reexamining Rationales of 'Fairness': An Athlete and Insider's Perspective on the New Policies on Hyperandrogenism in Elite Female Athletes" published by the American Journal of Bioethics in 2012, Martínez-Patiño and co-author Hida Viloria discussed current sex testing practices in sport. (wikipedia.org)
  • less
  • Sometimes symptoms are more prominent and may include weaker muscles, greater height, poor coordination, less body hair, breast growth, and less interest in sex. (wikipedia.org)