Other Names for this Disease
- Klinefelter's syndrome
- XXY syndrome
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Klinefelter syndrome is not inherited, but usually occurs as a random event during the formation of reproductive cells (eggs and sperm). An error in cell division called nondisjunction can result in reproductive cells with an abnormal number of chromosomes. For example, an egg or sperm cell may gain one or more extra copies of the X chromosome as a result of nondisjunction. If one of these reproductive cells contributes to the genetic makeup of a child, the child will have one or several extra X chromosomes in each of the body's cells.
Last updated: 10/12/2015
- Klinefelter syndrome. Genetics Home Reference. January 2013; http://ghr.nlm.nih.gov/condition=klinefeltersyndrome.