Home > 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.

1 External links

• http://www.47xxy.org/
• http://www.klinefeltersyndrome.org/
• http://www.aaksis.org/

2 See also

• Turner syndrome