Sex Chromosome Disorders: Clinical conditions caused by an abnormal sex chromosome constitution (SEX CHROMOSOME ABERRATIONS), in which there is extra or missing sex chromosome material (either a whole chromosome or a chromosome segment).Sex Chromosome Disorders of Sex Development: Congenital conditions of atypical sexual development associated with abnormal sex chromosome constitutions including MONOSOMY; TRISOMY; and MOSAICISM.Sex Chromosomes: The homologous chromosomes that are dissimilar in the heterogametic sex. There are the X CHROMOSOME, the Y CHROMOSOME, and the W, Z chromosomes (in animals in which the female is the heterogametic sex (the silkworm moth Bombyx mori, for example)). In such cases the W chromosome is the female-determining and the male is ZZ. (From King & Stansfield, A Dictionary of Genetics, 4th ed)Chromosome Disorders: Clinical conditions caused by an abnormal chromosome constitution in which there is extra or missing chromosome material (either a whole chromosome or a chromosome segment). (from Thompson et al., Genetics in Medicine, 5th ed, p429)Chromosomes: In a prokaryotic cell or in the nucleus of a eukaryotic cell, a structure consisting of or containing DNA which carries the genetic information essential to the cell. (From Singleton & Sainsbury, Dictionary of Microbiology and Molecular Biology, 2d ed)Sex Chromosome Aberrations: Abnormal number or structure of the SEX CHROMOSOMES. Some sex chromosome aberrations are associated with SEX CHROMOSOME DISORDERS and SEX CHROMOSOME DISORDERS OF SEX DEVELOPMENT.Chromosome Mapping: Any method used for determining the location of and relative distances between genes on a chromosome.X Chromosome: The female sex chromosome, being the differential sex chromosome carried by half the male gametes and all female gametes in human and other male-heterogametic species.Y Chromosome: The male sex chromosome, being the differential sex chromosome carried by half the male gametes and none of the female gametes in humans and in some other male-heterogametic species in which the homologue of the X chromosome has been retained.Chromosome Banding: Staining of bands, or chromosome segments, allowing the precise identification of individual chromosomes or parts of chromosomes. Applications include the determination of chromosome rearrangements in malformation syndromes and cancer, the chemistry of chromosome segments, chromosome changes during evolution, and, in conjunction with cell hybridization studies, chromosome mapping.Chromosomes, Human, X: The human female sex chromosome, being the differential sex chromosome carried by half the male gametes and all female gametes in humans.Chromosome Aberrations: Abnormal number or structure of chromosomes. Chromosome aberrations may result in CHROMOSOME DISORDERS.Chromosomes, Human, Y: The human male sex chromosome, being the differential sex chromosome carried by half the male gametes and none of the female gametes in humans.Sex Determination Processes: The mechanisms by which the SEX of an individual's GONADS are fixed.Chromosome Pairing: The alignment of CHROMOSOMES at homologous sequences.Chromosomes, Plant: Complex nucleoprotein structures which contain the genomic DNA and are part of the CELL NUCLEUS of PLANTS.Silene: A plant genus of the family CARYOPHYLLACEAE. The common name of campion is also used with LYCHNIS. The common name of 'pink' can be confused with other plants.X Chromosome Inactivation: A dosage compensation process occurring at an early embryonic stage in mammalian development whereby, at random, one X CHROMOSOME of the pair is repressed in the somatic cells of females.In Situ Hybridization, Fluorescence: A type of IN SITU HYBRIDIZATION in which target sequences are stained with fluorescent dye so their location and size can be determined using fluorescence microscopy. This staining is sufficiently distinct that the hybridization signal can be seen both in metaphase spreads and in interphase nuclei.Chromosome Segregation: The orderly segregation of CHROMOSOMES during MEIOSIS or MITOSIS.Chromosomes, Human: Very long DNA molecules and associated proteins, HISTONES, and non-histone chromosomal proteins (CHROMOSOMAL PROTEINS, NON-HISTONE). Normally 46 chromosomes, including two sex chromosomes are found in the nucleus of human cells. They carry the hereditary information of the individual.Karyotyping: Mapping of the KARYOTYPE of a cell.Chromosomes, Human, Pair 1: A specific pair of human chromosomes in group A (CHROMOSOMES, HUMAN, 1-3) of the human chromosome classification.Genes, Y-Linked: Genes that are located on the Y CHROMOSOME.Genes, X-Linked: Genes that are located on the X CHROMOSOME.Aneuploidy: The chromosomal constitution of cells which deviate from the normal by the addition or subtraction of CHROMOSOMES, chromosome pairs, or chromosome fragments. In a normally diploid cell (DIPLOIDY) the loss of a chromosome pair is termed nullisomy (symbol: 2N-2), the loss of a single chromosome is MONOSOMY (symbol: 2N-1), the addition of a chromosome pair is tetrasomy (symbol: 2N+2), the addition of a single chromosome is TRISOMY (symbol: 2N+1).Chromosomes, Human, Pair 21: A specific pair of GROUP G CHROMOSOMES of the human chromosome classification.Chromosomes, Artificial, Bacterial: DNA constructs that are composed of, at least, a REPLICATION ORIGIN, for successful replication, propagation to and maintenance as an extra chromosome in bacteria. In addition, they can carry large amounts (about 200 kilobases) of other sequence for a variety of bioengineering purposes.Chromosome Painting: A technique for visualizing CHROMOSOME ABERRATIONS using fluorescently labeled DNA probes which are hybridized to chromosomal DNA. Multiple fluorochromes may be attached to the probes. Upon hybridization, this produces a multicolored, or painted, effect with a unique color at each site of hybridization. This technique may also be used to identify cross-species homology by labeling probes from one species for hybridization with chromosomes from another species.Chromosomes, Bacterial: Structures within the nucleus of bacterial cells consisting of or containing DNA, which carry genetic information essential to the cell.Sex Characteristics: Those characteristics that distinguish one SEX from the other. The primary sex characteristics are the OVARIES and TESTES and their related hormones. Secondary sex characteristics are those which are masculine or feminine but not directly related to reproduction.Platypus: A small aquatic oviparous mammal of the order Monotremata found in Australia and Tasmania.Chromosomes, Human, Pair 7: A specific pair of GROUP C CHROMOSOMES of the human chromosome classification.Chromosomes, Insect: Structures within the CELL NUCLEUS of insect cells containing DNA.Meiosis: A type of CELL NUCLEUS division, occurring during maturation of the GERM CELLS. Two successive cell nucleus divisions following a single chromosome duplication (S PHASE) result in daughter cells with half the number of CHROMOSOMES as the parent cells.Chromosomes, Human, Pair 11: A specific pair of GROUP C CHROMOSOMES of the human chromosome classification.Chromosomes, Human, Pair 17: A specific pair of GROUP E CHROMOSOMES of the human chromosome classification.Chromosome Deletion: Actual loss of portion of a chromosome.Sex Chromatin: In the interphase nucleus, a condensed mass of chromatin representing an inactivated X chromosome. Each X CHROMOSOME, in excess of one, forms sex chromatin (Barr body) in the mammalian nucleus. (from King & Stansfield, A Dictionary of Genetics, 4th ed)

*  Hudson Reporter - About Zoemy… Local 2 year old has rare chromosome disorder plus four others

Her 2-year-old, Zoemy, has been diagnosed with a rare chromosome disorder that has no precedent and thus no prior medical ... Local 2-year-old has rare chromosome disorder plus four others - Noemi Alicea a Hoboken native is caring for two special needs ... Normal females have 46 chromosomes, with two sex chromosomes known as "X." Females with Turner Syndrome are missing one of ... Her 2-year-old, Zoemy, has been diagnosed with a rare chromosome disorder that has no precedent and thus no prior medical ...

*  Growth Hormone Therapy is Approved: for Patients with Chromosome Disorders

Mirena IUD and Your Sex Drive. By Gyno Gab - January 03, 2010 ... For women on an IUD sex drive changes are often reported. We ... Are you a pre-pubertal teen with Turners syndrome (lacking a double X to your chromosomes)? If so Growth Hormone is approved ... Women's health and wellness from a Board Certified Obstetrician and Gynecologist, topics from wellness, sex, to infertility, ...

*  What are the most common sex chromosome disorders? - Answered by top doctors on HealthTap

Is XYY syndrome- Sex-linked-yes or no; particular chromosome; recessive or more Is XYY syndrome- Sex-linked-yes or no; ... What are the most common sex chromosome disorders?. 3 doctors weighed in ... a sex-linked disorder or a type of mutation in a specific ch more Can you tell me is hurler's syndrome nondisjunction, a sex- ... sex-linked, or chromos more Can you tell me if the disorder, hypercholesterolemia, a recessive, dominant, coodominant, sex- ...

*  Category:Sex chromosome aneuploidies | Psychology Wiki | FANDOM powered by Wikia

Emotional Deprivation Disorder * List of personality traits * List of human resource management topics ... Pages in category "Sex chromosome aneuploidies". This category contains only the following page. ...

*  Sex Chromosomes: Genetics, Abnormalities, and Disorders

Sex chromosomes determine the sex of an organism. A human somatic cell has two sex chromosomes: XY in male and XX in female. A ... Chapter 1. Sex Chromosomes, Gender Differences and Disease, pp. 1-24 (Lopes AM, Sargent CA, Affara NA, Amorim A, Instituto de ... SRY (which stands for sex-determining region Y gene) is found on the Y chromosome. In the cell, it binds to other DNA and in ... Chapter 7. The W Chromosome Evolution and Sex-linked Gene Expression in the Japanese Frog Rana Rugosa, pp. 123-140 (Ikuo Miura ...

*  Blogarama - #1 Blog directory

What is a Sex Chromosome Disorder?. Be Healthy, Be Happy… · 03:13 23 Sep 2017 ... In each pair, one chromosome is inherited from each parent. One of these pairs is referred to as the sex chromosome pair ... Anxiety Disorders and Major Depression Are Linked To Narcissistic Abuse Read More ... What is the Difference Between Voice Problems (Voice Disorders) & Speech Problems (Speech Impediment)?. ...

*  Karyotypes, sex chromosomes and change of chromosome number - Revision Cards in University Biology

Other genes are present on the sex chromosomes than sex determinants. These can cause sex-linked disorders such as haemophilia ... Home > University > Biology > Karyotypes, sex chromosomes and change of chromosome number Karyotypes, sex chromosomes and ... Incidence of sex chromosome disorders is high. Caused by nondisjunction at anaphase I and II of meiosis. This causes some of ... Sex determination. Maleness in humans is caused by the presence of the Y chromosome not by the lack of a second X chromosome. ...

*  Identify three causes of chromosomal disorders - Answers on HealthTap

Ali on identify three causes of chromosomal disorders: The specific causes are unknown. It is however believed to be ... What are the most common sex chromosome disorders? Dr. George Klauber Dr. Klauber ... A chromosomal disorder is any disorder that involves a person's genetic makeup. Humans have 23 chromosomes that basically ... It's genetic: A chromosomal disorder is any disorder that involves a person's genetic makeup. Humans have 23 chromosomes that ...

*  Protein Synthesis in the Brain of Patients With Fragile X Syndrome - Full Text View - ClinicalTrials.gov

Sex Chromosome Disorders. Chromosome Disorders. Congenital Abnormalities. Genetic Diseases, Inborn. Genetic Diseases, X-Linked ... in the investigation of disorders of brain development, recovery from brain injury, and neurodegenerative diseases. ... in the investigation of disorders of brain development, recovery from brain injury, and neurodegenerative diseases. ...

*  Clinical and Molecular Characterisation of Orofaciodigital Syndromes and Other Clinical Phenotypes Secondary to Mutations in...

Sex Chromosome Disorders. Chromosome Disorders. Genetic Diseases, Inborn. ClinicalTrials.gov processed this record on September ...

*  Clinical Study to Assess the Pharmacokinetics, Safety and Tolerability of Single and Multiple Oral Doses of AFQ056 in Children...

Sex Chromosome Disorders. Chromosome Disorders. Congenital Abnormalities. Genetic Diseases, Inborn. Genetic Diseases, X-Linked ... or gastrointestinal disorders (except for typical features of FXS). ...

*  Safety and Efficacy of AFQ056 in Adolescent Patients With Fragile X Syndrome - Full Text View - ClinicalTrials.gov

Sex Chromosome Disorders. Chromosome Disorders. Congenital Abnormalities. Genetic Diseases, Inborn. Genetic Diseases, X-Linked ...

*  Randomized Controlled Study of Donepezil in Fragile X Syndrome - Full Text View - ClinicalTrials.gov

Sex Chromosome Disorders. Chromosome Disorders. Congenital Abnormalities. Genetic Diseases, Inborn. Genetic Diseases, X-Linked ... Current or lifetime DSM-IV diagnosis of bipolar disorder, schizophrenia, schizoaffective disorder, or psychotic disorder, NOS ... autism spectrum disorders (ASD) or anxiety disorders. These circumstances are suboptimal as such symptom-based treatments ... If found to be effective, the knowledge generated by this research may also be relevant to other developmental disorders that ...

*  Turner Syndrome: Genotype and Phenotype - Full Text View - ClinicalTrials.gov

Disorders of Sex Development. Urogenital Abnormalities. Sex Chromosome Disorders of Sex Development. Heart Defects, Congenital ... Sex Chromosome Disorders. Chromosome Disorders. Genetic Diseases, Inborn. Gonadal Disorders. Endocrine System Diseases. Ovarian ... One pair of chromosomes is the sex chromosomes, designated X and Y. Females usually have two X chromosomes; however, patients ... a disorder of the sex chromosomes. Humans usually have 23 pairs of chromosomes-thin strands of DNA-in the nucleus of every cell ...

*  A Study of RO4917523 in Pediatric Patients With Fragile X Syndrome - Full Text View - ClinicalTrials.gov

Sex Chromosome Disorders. Chromosome Disorders. Congenital Abnormalities. Genetic Diseases, Inborn. Genetic Diseases, X-Linked ...

*  National Registry of Genetically Triggered Thoracic Aortic Aneurysms and Cardiovascular Conditions - Full Text View -...

Disorders of Sex Development. Urogenital Abnormalities. Sex Chromosome Disorders of Sex Development. Heart Defects, Congenital ... Recurrent chromosome 16p13.1 duplications are a risk factor for aortic dissections. PLoS Genet. 2011 Jun;7(6):e1002118. doi: ... Autosomal and X chromosome structural variants are associated with congenital heart defects in Turner syndrome: The NHLBI ...

*  Turner Syndrome Prenatal Diagnosis Study - Full Text View - ClinicalTrials.gov

Disorders of Sex Development. Urogenital Abnormalities. Sex Chromosome Disorders of Sex Development. Heart Defects, Congenital ... Sex Chromosome Disorders. Chromosome Disorders. Genetic Diseases, Inborn. Gonadal Disorders. Endocrine System Diseases. Ovarian ...

*  Dry Eye in Women With Turner Syndrome and Women With Premature Ovarian Failure - Full Text View - ClinicalTrials.gov

Disorders of Sex Development. Urogenital Abnormalities. Sex Chromosome Disorders of Sex Development. Heart Defects, Congenital ... Chromosome Aberrations. Chromosome Disorders. Sex Chromosome Aberrations. Disease. Pathologic Processes. Obstetric Labor, ... Sex Chromosome Disorders. Genetic Diseases, Inborn. Gonadal Disorders. Endocrine System Diseases. Ovarian Diseases. Adnexal ... Ocular Impact of X Chromosome Karyotype and Sex Hormones in Turner Syndrome. ...

*  Add-on Pilot Trial of Minocycline to Treat Fragile X Syndrome - Full Text View - ClinicalTrials.gov

Sex Chromosome Disorders. Chromosome Disorders. Congenital Abnormalities. Genetic Diseases, Inborn. Genetic Diseases, X-Linked ... these structures may represent an anatomical and physiological basis for the cognitive deficits associated with this disorder. ...

*  The Natural History of Reproductive and Overall Health in Girls and Women With a Pre-Mutation in the FMR1 Gene; Creation of a...

Sex Chromosome Disorders. Chromosome Disorders. Congenital Abnormalities. Genetic Diseases, Inborn. Genetic Diseases, X-Linked ... Heredodegenerative Disorders, Nervous System. Ovarian Diseases. Adnexal Diseases. Genital Diseases, Female. Gonadal Disorders. ... neurological disorders, and psychiatric disorders. A patient registry will also allow us to track development of these and ... The FMR1 gene is located on the X-chromosome and contains a CGG repeat in the un-translated region; this CGG repeat is normally ...

*  Effect of Biosynthetic Growth Hormone and/or Ethinyl Estradiol on Adult Height in Patients With Turner Syndrome - Full Text...

Disorders of Sex Development. Urogenital Abnormalities. Sex Chromosome Disorders of Sex Development. Heart Defects, Congenital ... Sex Chromosome Disorders. Chromosome Disorders. Genetic Diseases, Inborn. Gonadal Disorders. Endocrine System Diseases. Ovarian ... In normal girls the ovaries begin producing small amounts of the female sex hormone, estrogen at about 11 - 12 years of age. As ... Turners Syndrome is a genetic condition in females that is a result of abnormal chromosomes. Girls with Turner syndrome are ...

*  Safety and Efficacy Study of Antioxidants for the Treatment of the Fragile X Syndrome - Full Text View - ClinicalTrials.gov

Sex Chromosome Disorders. Chromosome Disorders. Congenital Abnormalities. Genetic Diseases, Inborn. Genetic Diseases, X-Linked ... Bell in 1943, in families with several patients affected by sex-linked mental disability. This disorder is the most common ... Heredodegenerative Disorders, Nervous System. Vitamins. Ascorbic Acid. Vitamin E. Tocopherols. Tocotrienols. alpha-Tocopherol. ... The study excludes individuals with other neurological disorders not linked to the syndrome. ...

*  Sex Differences in Early Brain Development; Brain Development in Turner Syndrome - Full Text View - ClinicalTrials.gov

Disorders of Sex Development. Urogenital Abnormalities. Sex Chromosome Disorders of Sex Development. Heart Defects, Congenital ... Sex Chromosome Disorders. Chromosome Disorders. Genetic Diseases, Inborn. Gonadal Disorders. Endocrine System Diseases. Ovarian ... a well-defined genetic disorder resulting from the partial or complete loss of one of the sex chromosomes. To address aim 1, ... It has been hypothesized that the prevalence and expression of these disorders is related to sex differences in brain ...

*  Effects of CX516 on Functioning in Fragile X Syndrome and Autism - Full Text View - ClinicalTrials.gov

Sex Chromosome Disorders. Chromosome Disorders. Congenital Abnormalities. Genetic Diseases, Inborn. Genetic Diseases, X-Linked ... Child Development Disorders, Pervasive. Neurodevelopmental Disorders. Mental Disorders. Mental Retardation, X-Linked. ... Autistic Disorder. Fragile X Syndrome. Disease. Pathologic Processes. ... these changes caused by CX516 could be helpful in managing cognitive and behavioral symptoms in patients with autistic disorder ...

*  Hereditary sideroblastic anemia

... on chromosome 14q32; and SIDBA4 ({182170}), caused by mutation in the HSPA9 gene ({600548}) on chromosome 5q31. Source: Online ... The age of clinical onset of the disorder can vary from in utero to the ninth decade. Whereas males are preferentially affected ... Detailed clinical and genetic studies have been performed in a Negro family, which segregated for sex-linked sideroblastic ... on chromosome 3p22; SIDBA3 ({616860}), caused by mutation in the GLRX5 gene ({609588}) ...

Premature chromosome condensation: Premature chromosome condensation (PCC) occurs in eukaryotic organisms when mitotic cells fuse with interphase cells. Chromatin, a substance that contains genetic material such as DNA, is normally found in a loose bundle inside a cell's nucleus.Chromosome regionsSmith–Fineman–Myers syndrome: Smith–Fineman–Myers syndrome (SFMS1), also called X-linked mental retardation-hypotonic facies syndrome 1 (MRXHF1), Carpenter–Waziri syndrome, Chudley–Lowry syndrome, SFMS, Holmes–Gang syndrome and Juberg–Marsidi syndrome (JMS), is a rare X-linked recessive congenital disorder that causes birth defects. This syndrome was named after 3 men, Richard D.PCDHY: PCDH11Y is a gene unique to human males which competes with FOXP2 for the title of the "language gene." PCDH11Y is the gene for making Protocadherin 11Y, a protein that guides the development of nerve cells.Genetic imbalance: Genetic imbalance is to describe situation when the genome of a cell or organism has more copies of some genes than other genes due to chromosomal rearrangements or aneuploidy.Suresh Jayakar: Suresh Dinakar Jayakar (21 September 1937, Bombay-21 January 1988) was an Indian biologist who pioneered in the use of quantitative approaches in genetics and biology.Silene undulataImmortal DNA strand hypothesis: The immortal DNA strand hypothesis was proposed in 1975 by John Cairns as a mechanism for adult stem cells to minimize mutations in their genomes.Cairns, J.Circular bacterial chromosome: A circular bacterial chromosome is a bacterial chromosome in the form of a molecule of circular DNA. Unlike the linear DNA of most eukaryotes, typical bacterial chromosomes are circular.Platypus venom

(1/41) ARX, a novel Prd-class-homeobox gene highly expressed in the telencephalon, is mutated in X-linked mental retardation.

Investigation of a critical region for an X-linked mental retardation (XLMR) locus led us to identify a novel Aristaless related homeobox gene (ARX ). Inherited and de novo ARX mutations, including missense mutations and in frame duplications/insertions leading to expansions of polyalanine tracts in ARX, were found in nine familial and one sporadic case of MR. In contrast to other genes involved in XLMR, ARX expression is specific to the telencephalon and ventral thalamus. Notably there is an absence of expression in the cerebellum throughout development and also in adult. The absence of detectable brain malformations in patients suggests that ARX may have an essential role, in mature neurons, required for the development of cognitive abilities.  (+info)

(2/41) X chromosome dosage by quantitative fluorescent PCR and rapid prenatal diagnosis of sex chromosome aneuploidies.

During the past few years, rapid prenatal diagnosis of chromosome aneuploidies has been successfully achieved by quantitative fluorescent PCR (QF-PCR) amplification of chromosome-specific small tandem repeats (STR). This approach has proven to be very useful in clinical settings, since it allows the detection of major numerical disorders in a few hours after sampling. For the detection of Turner's syndrome (45,X), several highly polymorphic STR on the X chromosome are needed in order to reduce the likelihood that a normal female might be homozygous for all sequences and, consequently, that the test could fail to discriminate between samples retrieved from a Turner's and a normal female fetus. Here we report a new method for rapid and accurate detection of X chromosome copy number in prenatal samples that does not depend on STR heterozygosity. The test is based on QF-PCR amplification of the X-linked HPRT together with the autosomal D21S1411 used as internal control for quantification. In the course of this study, this assay allowed the prenatal diagnosis of a rare case of a normal female homozygous for four selected highly polymorphic X chromosome STR, as well as the assessment of the normal chromosome complement of a fetus homozygous for five chromosome 21 markers.  (+info)

(3/41) Reproductive genetic counselling in non-mosaic 47,XXY patients: implications for preimplantation or prenatal diagnosis: Case report and review.

With an incidence of approximately 1 in 500 male newborns, the 47,XXY genotype is one the most common sex chromosome anomalies. It is also the most frequent genetic cause of human infertility. Some non-mosaic 47,XXY patients have sperm production which allows infertility treatment to be offered by ICSI. Therefore, the risk of transmitting a chromosome anomaly to the next generation is an important problem in reproductive genetic counselling of these patients. Here, we report on a twin pregnancy where two karyotypically normal neonates 46,XX and 46,XY were born after the use of ICSI in assisted reproduction of a patient with a non-mosaic 47,XXY syndrome. To date, only 38 evolving pregnancies including the present cases, have been reported after ICSI using sperm from non-mosaic 47,XXY patients. Although these data are scarce, they suggest that the risk of chromosome anomaly in the offspring of these patients is low; hence, their reproductive genetic counselling can be reassuring, and management of the pregnancy can proceed with caution.  (+info)

(4/41) The genetic basis of infertility.

Infertility is defined as the inability to conceive after one year of regular unprotected intercourse; approximately one in six couples wishing to start a family fall into this category. Although, in many cases, the diagnosis is simply 'unexplained', a variety of reasons including lack of ovulation, mechanical stoppage, sperm deficiencies and parental age have been implicated. It is difficult to assess accurately the overall magnitude of the contribution of genetics to infertility as most, if not all, conditions are likely to have a genetic component, for example susceptibility to infection. Nevertheless, a significant number of infertility phenotypes have been associated with specific genetic anomalies. The genetic causes of infertility are varied and include chromosomal abnormalities, single gene disorders and phenotypes with multifactorial inheritance. Some genetic factors influence males specifically, whereas others affect both males and females. For example, chromosome translocations affect both males and females, whereas Klinefelter syndrome and the subsequent infertility phenotype caused by it are specific to males. This article reviews current research in the genetic basis of infertility; gender-specific disorders and those affecting both sexes are considered.  (+info)

(5/41) Rapid and simple prenatal diagnosis of common chromosome disorders: advantages and disadvantages of the molecular methods FISH and QF-PCR.

Molecular techniques have been developed for prenatal diagnosis of the most common chromosome disorders (trisomies 21, 13, 18 and sex chromosome aneuploidies) where results are available within a day or two. This involves fluorescence in situ hybridization (FISH) and microscopy analysis of fetal cells or quantitative fluorescence polymerase chain reaction (QF-PCR) on fetal DNA. Guidance is provided on the technological pitfalls in setting up and running these methods. Both methods are reliable, and the risk for misdiagnosis is low, although slightly higher for FISH. FISH is also more labour intensive than QF-PCR, the latter lending itself more easily to automation. These tests have been used as a preamble to full chromosome analysis by microscopy. However, there is a trend to apply the tests as 'stand-alone' tests for women who are at relatively low risk of having a baby with a chromosome disorder, in particular that associated with advanced age or results of maternal serum screening programmes. These women comprise the majority of those currently offered prenatal diagnosis with respect to fetal chromosome disorders and if introduced on a larger scale, the use of FISH and QF-PCR would lead to substantial economical savings. The implication, on the other hand, is that around one in 500 to one in 1000 cases with a mentally and/or physically disabling chromosome disorder would remain undiagnosed.  (+info)

(6/41) A case of 49,XXXXX in which the extra X chromosomes were maternal in origin.

This report describes an 11 month old female baby with features of pentasomy X. A molecular and cytogenetic evaluation revealed that her karyotype was 49,XXXXX and her extra X chromosomes were of maternal origin. She has muscular hypotonia, mental retardation, a cleft palate, mild hydrocephalus as a result of dilatation of both lateral ventricles, hyperextensible elbow joints, proximal radioulnar synostosis, clinodactyly of the fifth finger, valgus of the feet, and small hands and feet. In addition, she has a persistent pupillary membrane and congenital chorioretinal atrophy. The pathogenesis of pentasomy X is not clear at present, but it is thought to be caused by successive maternal non-dysjunctions.  (+info)

(7/41) 49, XXXXY syndrome.

49, XXXXY syndrome is a rare sex chromosomal disorder. A 5-month-old boy had failure to thrive and multiple congenital anomalies including microcephaly, facial dysmorphism (hypertelorism, megacornea, cleft palate, and micrognathia), obvious heart murmur, umbilical hernia, microphallus, and mild clenched hands. Chromosomal studies via techniques of G-banding and fluorescence in situ hybridization showed the constitution to be 47, XXXXY in all cells. Ventriculomegaly and congenital cardiac defects (patent ductus arteriosus, atrial septal defect, and peripheral pulmonary stenosis) were noted. He has severe atopic dermatitis with high IgE levels and psychomotor retardation. After heart surgery and nutritional support, he has better growth and the rehabilitation program is continuing.  (+info)

(8/41) Fate of SRY, PABY, DYS1, DYZ3 and DYZ1 loci in Indian patients harbouring sex chromosomal anomalies.

We analysed chromosomes, conducted hormonal assays and screened genomic DNA of 34 patients with or without detectable Y chromosome for the presence/absence of SRY, PABY, DYS1, DYZ3 and DYZ1 loci and for mutations in the SRY gene. The samples studied represented cases of oligozoospermia, cryptorchidism, Swyer syndrome, Turner syndrome, male pseudohermaphroditism, XXY female syndrome, Klinefelter's syndrome, repeated abortion and instances of male infertility. Chromosomal constitutions and the level of hormones (FSH, LH, PRL, E2 and TSH) were found to be abnormal in several cases. A phenotypic female (P20) positive for all the Y-linked loci screened, showed mutations upstream of the HMG box in the SRY gene. In addition, one or more of the Y-linked loci were detected in several phenotypic females. Fluorescence in-situ hybridization of metaphase chromosomes and interphase nuclei of an aborted fetus with DYZ1 probe detected signals from normal to low levels to its complete absence confirming a complex Y chromosome mosaicism. Upon DNA analysis, the fetus was found to be positive for all the above-mentioned Y-linked loci. Organizational variation within the DYZ1 arrays and its correlation with recurrent spontaneous abortion may be followed-up in subsequent studies to substantiate this observation. This would augment genetic counselling to the affected couples. Prospects of this approach in the overall management of clinical cases with sex chromosome-related anomalies are discussed.  (+info)



Abnormalities

  • Are genetic disorders associated with abnormalities of autosomes or sex chromosomes? (healthtap.com)
  • What are some common chromosome abnormalities? (healthtap.com)
  • Obvious from studying sex chomosome abnormalities such as Klinefelter syndrome (causes XXY males) and Turner syndrome (causes X females). (getrevising.co.uk)
  • The normal impact of chromosome abnormalities is the interruption of complex fetal organ development. (healthtap.com)

karyotype

  • Chromosomes are arranged in order of size and the position of the centromer to give the karyotype or chromosome complement of the individual. (getrevising.co.uk)
  • The karyotype varies according to the sex. (getrevising.co.uk)

autosomes

  • Autosomes can also suffer nondisjuction at meiosis which gives rise to aneuploidy where the chromosome number is not an exact multiple of the haploid number. (getrevising.co.uk)

humans

  • Humans have 46 chromosomes but males have two that are not a pair. (getrevising.co.uk)
  • Maleness in humans is caused by the presence of the Y chromosome not by the lack of a second X chromosome. (getrevising.co.uk)
  • Humans have 23 chromosomes that basically determine everything about an individual. (healthtap.com)
  • Fragile X syndrome (FraX), a neurodevelopmental disorder caused by mutations of the FMR1 gene, is the most common known heritable cause of cognitive and behavioral disability in humans. (clinicaltrials.gov)
  • Humans usually have 23 pairs of chromosomes-thin strands of DNA-in the nucleus of every cell, which contain genes that determine our hereditary makeup. (clinicaltrials.gov)

Chromosomal

  • Most XX men who lack a Y chromosome do still have a copy of the SRY gene on one of their X chromosomes (moved there by chromosomal translocation). (novapublishers.com)
  • Is There Always the Agreement of Chromosomal and Phenotypic Sex? (novapublishers.com)
  • Is Down Syndrome a sex linked chromosomal disease? (healthtap.com)
  • Can you tell me the following human disorders that result from chromosomal alterations? (healthtap.com)
  • What are some chromosomal disorders? (healthtap.com)
  • A chromosomal disorder is any disorder that involves a person's genetic makeup. (healthtap.com)
  • have a chromosomal disorder. (healthtap.com)
  • What are some x and y chromosomal disorders? (healthtap.com)
  • Should I get testing for chromosomal disorders? (healthtap.com)
  • Do I need to have testing for chromosomal disorders? (healthtap.com)
  • What is the definition or description of: chromosomal disorders? (healthtap.com)
  • If part of a chromosome is missing or duplicated or mutated, then we have a chromosomal disorder. (healthtap.com)
  • Are any chromosomal disorders terminal? (healthtap.com)
  • The most common cause in infants ( chromosomal disorders . (healthtap.com)
  • Are chromosomal disorders considered as autism? (healthtap.com)
  • Are life-threatening chromosomal disorders usually detected in early infancy? (healthtap.com)

abnormality

  • From preliminary data, we suspect that women with Turners syndrome (45, XO), a genetic abnormality that affects sex hormone levels, are also at increased risk of ocular surface disease. (clinicaltrials.gov)

Eligible

  • Females 10 years of age and older with X chromosome defects may be eligible for this 3- to 5- day inpatient study at the National Institutes of Health Clinical Center in Bethesda, Maryland. (clinicaltrials.gov)

developmental disorders

  • The physiological and developmental disorders caused are more severe than for sex chromosomes. (getrevising.co.uk)
  • If found to be effective, the knowledge generated by this research may also be relevant to other developmental disorders that share common disease pathways with FraX. (clinicaltrials.gov)
  • Like many other developmental disorders, descriptions of treatments for FraX that do exist in the literature are primarily derived from uncontrolled case studies or series, with both pharmacological and behavioral interventions targeted to symptoms associated with phenomenologically defined 'co-morbid' diagnoses such as AD/HD, autism spectrum disorders (ASD) or anxiety disorders. (clinicaltrials.gov)

genetic

  • What chromosomes cause the genetic disorder achondroplasia? (healthtap.com)
  • This study examines the clinical and genetic factors related to Turner syndrome, a disorder of the sex chromosomes. (clinicaltrials.gov)
  • Turners Syndrome is a genetic condition in females that is a result of abnormal chromosomes. (clinicaltrials.gov)

abnormal

  • Individuals with Turner syndrome have an increased risk of thyroid disorders, high blood pressure, diabetes mellitus, abnormal liver function, hearing loss and osteoporosis. (clinicaltrials.gov)
  • Women at least 18 years of age who have an abnormal FMR1 gene on the X chromosome. (clinicaltrials.gov)

organism

  • Sex chromosomes determine the sex of an organism. (novapublishers.com)
  • Polyploids are organism with more than one complete set of chromosomes e.g triploids (3n) and tetraploids (4n). (getrevising.co.uk)

females

  • Normal development requires a balanced set of chromosomes but the X chromosome is present twice in females and only once in males. (getrevising.co.uk)

determination

  • Analysis of such individuals has revealed some of the molecules involved in sex determination, including one called SRY, which is important for testis formation. (novapublishers.com)

Turner

  • however, patients with Turner syndrome have only a single X chromosome or one normal and one defective X or Y chromosome. (clinicaltrials.gov)

genes

  • Other genes are present on the sex chromosomes than sex determinants. (getrevising.co.uk)
  • This study will try to identify the genes responsible for the specific medical problems associated with the disorder. (clinicaltrials.gov)

turners

  • You can have too many y chromosomes (klinefelters) or a missing x (turners). (healthtap.com)

Disease

autism

  • Many kids with chromosome disorders have difficulties with communication and behavior and function similar to autistic or pdd patients in the autism spectrum. (healthtap.com)
  • The Autism Diagnostic Observation Schedule (ADOS-2) assesses and diagnoses autism spectrum disorder. (clinicaltrials.gov)

Syndrome

  • You can have extra y chromosomes termed klinefelter's syndrome and you can have only one x termed turner's syndrome. (healthtap.com)

involves

  • Similar chromosomes can be distinguished by the horizontal banding patterns formed by quinacrine staining or chromosome painting (involves tagging with fluorescent dyes). (getrevising.co.uk)

occur

  • Hermaphroditism can also occur in 46 xx individuals with a fragment of a y chromosome. (healthtap.com)
  • Extra x chromosomes can occur but usually are normal. (healthtap.com)

determine

  • How do our chromosomes determine our sex? (healthtap.com)
  • Your chromosomes determine what color your eyes are, your hair color, but also your internal organs. (healthtap.com)

gene

  • SRY (which stands for sex-determining region Y gene) is found on the Y chromosome. (novapublishers.com)
  • The Y chromosome actively diverts the undifferentiated gonad in the developing embryo there is evidence of a testis-determining gene. (getrevising.co.uk)

female

  • A human somatic cell has two sex chromosomes: XY in male and XX in female. (novapublishers.com)
  • At meiosis in a female the two X chromosomes form a bivalent and separate as an autosome. (getrevising.co.uk)
  • A dosage compensation mechanism operates to inactivate one of the X chromosomes in female cells. (getrevising.co.uk)
  • In normal girls the ovaries begin producing small amounts of the female sex hormone, estrogen at about 11 - 12 years of age. (clinicaltrials.gov)

cause

child

  • Maternal age over 35, prior child with a disorder, certain family histories, or depending on your ethnic background, you may need or choose testing. (healthtap.com)

common

  • What are the most common sex chromosome disorders? (healthtap.com)
  • At meiosis in the male the X and Y chromosome pair at a short pseudoautosomal region common to the tips of the chromosome. (getrevising.co.uk)

impact

Usually

  • Combination of a Y-sperm and an egg will produce a male.Usually, a woman has two X chromosomes (XX) and a man one X and one Y (XY). (novapublishers.com)

high

causes

  • This causes some of the gametes to be unbalanced as both sex chromosomes will pass to one daughter nucleus. (getrevising.co.uk)

However

  • However, because the remainder of the Y chromosome is missing they frequently do not develop secondary sexual characteristics in the usual way. (novapublishers.com)

human

  • A human germ cell has one sex chromosome: X or Y in a sperm and X in an egg. (novapublishers.com)

clinical

  • Ultimately the method may have widespread applications, not only for the study of normal development and plasticity but also in clinical medicine, e.g., in the investigation of disorders of brain development, recovery from brain injury, and neurodegenerative diseases. (clinicaltrials.gov)

similar

  • They show a criss-cross pattern through generations similar to the transmission of sex chromosomes. (getrevising.co.uk)

blood

  • For age matched control population ONLY- oral contraceptives or menopausal hormone therapy or any medications which alter sex hormone levels in the blood or chronic usage of medications that induce dry eye. (clinicaltrials.gov)

copy

  • Trisomy is the appearance of three copies of a particular chromosome and monosomy is when there is only one copy of a particular chromosome. (getrevising.co.uk)