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|Klinefelter's Syndrome (XXY Condition)|
Klinefelter syndrome is a condition that occurs in men as a result of an extra X chromosome. It is found in about 1 out of every 500-1,000 newborn males.
Humans have 46 chromosomes, which contain all of a person's genes and DNA. Two of these chromosomes, the sex chromosomes, determine a person's gender. Both of the sex chromosomes in females are called X chromosomes. (This is written as XX.) Males have an X and a Y chromosome (written as XY). The two sex chromosomes help a person develop fertility and the sexual characteristics of their gender.
Most often, Klinefelter syndrome is the result of one extra X (written as XXY). Occasionally, variations of the XXY chromosome count may occur, the most common being the XY/XXY mosaic. In this variation, some of the cells in the male's body have an additional X chromosome, and the rest have the normal XY chromosome count. The percentage of cells containing the extra chromosome varies from case to case. In some instances, XY/XXY mosaics may have enough normally functioning cells in the testes to allow them to father children.
Males who have Klinefelter syndrome may have the following symptoms: small, firm testes, a small penis, sparse pubic, armpit and facial hair, enlarged breasts (called gynecomastia), tall stature, and abnormal body proportions (long legs, short trunk).
As babies, many XXY males have weak muscles and reduced strength. As boys, between 25 percent and 85 percent of XXY males have some kind of language problem, such as learning to talk late, trouble using language to express thoughts and needs, problems reading, and trouble processing what they hear. Most XXY males are not able to father children (infertile).
Klinefelter syndrome is associated with an increased risk for breast cancer, a rare tumor called extragonadal germ cell tumor, lung disease, varicose veins and osteoporosis. Men who have Klinefelter syndrome also have an increased risk for autoimmune disorders such as lupus, rheumatoid arthritis and Sjogren's syndrome.
The XXY chromosome pattern can not be changed. But, there are a variety of ways to treat the symptoms of the XXY condition.
One of the most important factors for all types of treatment is starting it as early in life as possible.