Klinefelter's syndrome is a very common genetic disorder in which a man is born with an additional X chromosome. In some cases, more than one extra X chromosome may be present. This condition is also sometimes referred to as XXY, referencing the arrangement of sex chromosomes in people who have it, although Klinefelter's syndrome can also take the form of XXYY, or other configurations.
The condition was first described in 1942 by Doctor Henry Klinefelter. It is estimated that around one in every 500 males has Klinefelter's syndrome. The condition is congenital, caused by abnormalities in embryonic development, and it can cause a wide variety of symptoms. Not all patients experience the same medical issues in association with Klinefelter's syndrome, which can make it difficult to recognize.
Physically, men with this condition tend to be weaker and somewhat taller than their counterparts, and they may have slightly androgynous appearances, especially around the face. Occasionally, patients may develop extra breast tissue, and in around one in 10 cases, this breast tissue can be substantial enough for surgical treatment to be recommended. Some patients also experience shyness and social awkwardness, and cognitive impairments, especially with language processing, are not uncommon.
People are often unaware that they have Klinefelter's syndrome until they want to have children. The condition causes a decline in the production of testosterone, which results in limited fertility, and a diagnosis of Klinefelter's syndrome may be arrived at when a couple goes to a fertility doctor to understand why they are having trouble with their attempts at getting pregnant. In other cases, the condition may be diagnosed at an earlier age, usually as a result of the emergence of several symptoms which make a doctor suspicious.
It is not possible to cure an XXY male of the condition, but he can take steps to reduce the effects of Klinefelter's syndrome on his life. Taking testosterone injections during puberty can result in more conventional physical development, for example, and speech therapy can help with language issues. If infertility is a cause of distress, it is sometimes possible to reproduce with assisted methods in which sperm are extracted and utilized in the fertilization of an egg.
Many men with this condition live healthy, active lives, and they may be totally unaware of their slightly unusual chromosomes. A diagnosis with Klinefelter's syndrome is not the end of the world by any means, and it often results in fairly minimal disruption to a man's life.