Navigation Links
Klinefelter's syndrome

Klinefelter's syndrome is a condition caused by a chromosome abnormality in males (specifically, a nondisjunction); sufferers have a pair of X sex chromosomes instead of just one. It is named after Harry Klinefelter , the medical researcher who first described this syndrome in 1942.

Human males usually have an XY karyotype. The XXY chromosome arrangement is one of the most common genetic abnormalities, occurring in about 1 in 1,000 male births, but the symptoms that may result from having the extra chromosome are less common. Because of this extra chromosome, individuals with the abnormality are usually referred to as "XXY Males" rather than as "suffering from Klinefelter's syndrome."

In mammals with more than one X chromosome, the genes on all but one X chromosome are barred from being expressed. This happens in XXY males as well as XX females. A few genes, however, have corresponding genes on the Y chromosome and are not barred. These triploid genes in XXY males may be responsible for the symptoms of Klinefelter's syndrome.

In adults, the syndrome is characterised by gynecomastia (enlarged breasts), a rounded body type with abnormal body proportions, sparse facial and body hair, small testes, and an inability to produce sperm. Most XXY males have some degree of language impairment as well. The syndrome is associated with an increased risk of breast cancer, pulmonary disease , varicose veins, and osteoporosis.

The condition was identified in 1942 by Dr. Harry Klinefelter in Boston. The cause was not found until the 1950s. The condition is incurable, but its symptoms can be treated in a number of ways, including testosterone treatment and other therapies.

While the gender identity of people with XXY karyotype is usually male, the number of people with a female gender identity among them seems to be higher than could statistically be expected if those cases were indeed, as the current medical opinion assesses, mere coincidences of people having both gender identity disorder and Klinefelter's independently from each other. This observation however is based on the reports of support groups for transgender and transsexual people, no scientific study on this subject has been done. The fact that a person undergoing treatment for gender identity disorder has Klinefelter's syndrome is often missed or the patient is not told, although in many jurisdictions this additional diagnosis can have legal consequences, for example regarding name change. Also, the medical treatment may have to be adapted.

External links

See also


(Date:9/28/2015)... 28, 2015 The global ... USD 12.03 billion by 2020, growing at a CAGR ... as Backside Illumination (BSI) technique to improve picture quality ... period.      (Logo: , ... to reduce loss and, thus, reduce the noise interference ...
(Date:9/26/2015)... 26th, 2015  Results of a TactioRPM pilot ... today at the Stanford Medicine X Conference. In ... Dashboards, Connected Health Devices and Pharmacogenomics", Roger ... will explain how senior patients equipped with connected ... pharmacist via the TactioRPM remote patient monitoring platform ...
(Date:9/10/2015)... This report provides detailed descriptions of the sensor types ... types that will dominate in the future. Many product ... technology hype curve in the last five years before ... all of them is the prominence of sensor options ... Sensors collect data about the physical and chemical properties ...
Breaking Biology News(10 mins):Image Sensors Market Size to Reach $12.03 Billion By 2020: Grand View Research, Inc. 2Image Sensors Market Size to Reach $12.03 Billion By 2020: Grand View Research, Inc. 3Image Sensors Market Size to Reach $12.03 Billion By 2020: Grand View Research, Inc. 4Image Sensors Market Size to Reach $12.03 Billion By 2020: Grand View Research, Inc. 5Results of TactioRPM Pilot in a Senior Home Unveiled at Stanford Med X Conference 2Results of TactioRPM Pilot in a Senior Home Unveiled at Stanford Med X Conference 3Wearable Sensors 2015-2025: Market Forecasts, Technologies, Players 2
... limited by the seasons, particularly in colder climates ... researchers and fruit breeders, newly developed varieties are ... produce fruit during the offseasonresulting in economic bonuses ... the new varieties of blackberry called "primocane-fruiting", which ...
... The roe of hake, lumpsucker and salmon is the best dietary ... researchers at the University of Almera (UAL). The scientists analysed the ... these contained high levels of these fatty acids, which are essential ... precise understanding of the nutritional potential of the roe of marine ...
... , SAN DIEGO, ... has converted part of an existing building (Keen Hall), including ... cell core facility for the University of California, Riverside. ... , "A key project element was to ensure that although ...
Cached Biology News:New management methods extend blackberry season 2Roe of marine animals is best natural source of omega-3 2Kornberg Associates | Architects Completes UC Riverside Stem Cell Core Facility Project 2
Other biology definitionOther Tags