Klinefelter syndrome (KS) is a sex chromosome variation caused by the presence of one or more supernumerary X chromosomes. Common clinical phenotypes of KS are comprised of tall stature with a feminine body type, gynecomastia, small testes and infertility. Cases of KS with genital differences as the main evaluation in childhood are rarely disclosed. We … Continue reading Recognition of Genital Differences Among Some 47XXY Infants
Klinefelter syndrome (KS) is the most common sex-chromosome variation among males, with an estimated prevalence of 1:660 newborns. The most common karyotype is the classic 47,XXY, which accounts for the 80–90% of all cases. It is a consequence of a non-disjunction of paired X-chromosomes during the first or second meiotic division, equally due to a … Continue reading Evidence For Long Noncoding RNA Up-regulation in Klinefelter Syndrome
Original work on Turner syndrome included only women, but a number of published articles identified similar symptom clusters in male individuals. Original work on Klinefelter’s syndrome included only men. Significantly, Klinefelter (1986) always maintained that individuals with this syndrome cluster were unproblematically phenotypic males ‘and should never be considered otherwise’ . However, genetic science in the 1950s would significantly change the classification of individuals with diagnoses of Turner or Klinefelter’s syndromes.
The easiest way to distinguish male from female was to count the smallest chromosomes. If there were four, then they assumed that the sample came from a female; if five, then a male. After verifying this assumption with the recorded sex of the samples, they examined cells in a bone marrow sample taken from a Klinefelter’s syndrome patient.
It turns out that the rigid "line in the sand" over which the human sex chromosomes -- the Y and X -- go to avoid crossing over is a bit blurrier than previously thought. Contrary to the current scientific consensus, Arizona State University assistant professor Melissa Wilson Sayres has led a research team that has … Continue reading Human Sex Chromosome Swapping Occurs More Often Than Previously Thought
Since the beginning of humanity, people were fascinated by sex and intrigued by how the differences between sexes are determined. Ancient philosophers and middle age scholars proposed numerous fantastic explanations for the origin of sex differences in people and animals. However, only the development of the modern scientific methods allowed us to find, on the … Continue reading History of The Research on Sex Determination
Klinefelter syndrome (KS) is the one of the most frequent chromosomal disorder affecting 1/500–600 male newborns in the general population. The vast majority of the cases shows the 47,XXY karyotype, although mosaicism (46,XY/47,XXY) or higher-grade X aneuploidies can be rarely detected. Despite its high incidence, KS frequently remains undiagnosed and it is suspected later in … Continue reading Fertility Rates Among Non-Mosaic XXY; At Odds With Real Life Experience
Sex chromosome variations (SCV) are characterised by an atypical variation in the number or function of sex chromosomes. They are some of the most common genetic differences in human beings, and include 47 XXY; one in six hundred live births, 45X ; one in two thousand and 47 XYY; one in one thousand. However, by … Continue reading Cognitive and Neurological Aspects of Sex Chromosome Variations
Given the treatment of XXY individuals is (questionably) a sub speciality of Endocrinology it is envisaged that XXY's regardless of how they identify their gender would be exposed to the same difficulties experienced by GD and Trans Individuals.If you are an XXY individual we would love to hear of any difficulties you are experiencing with … Continue reading NHS in Disarray with Dispensing Hormones
https://www.youtube.com/watch?v=gcz1FOWw0Cg Confused with how chromosome numbers change in mitosis and meiosis? The Amoeba Sisters walk you through the mystery of chromosome and chromatid counting in mitosis and meiosis.
https://www.youtube.com/watch?v=zJbTdqiHdTQ The GEMINI project, or Genetics E learning for Medicine In Ireland aims to increase awareness of genetic conditions, genetic testing and diagnosis amongst healthcare professionals via educational presentations, videos and media and to assist in integrating tertiary genetics practice with mainstream medicine.