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Other Names for this Disease
- Klinefelter's syndrome
- XXY syndrome
- XXY trisomy
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Klinefelter syndrome is a chromosomal disorder that occurs in men and is typically caused by the presence of an additional X chromosome. Men with Klinefelter syndrome have two copies of the X chromosome, instead of the usual one copy. The extra chromosome X may affect physical, social, and language development. Symptoms differ from person to person. Treatment may include testosterone replacement therapy.
- Learning about Klinefelter syndrome. National Human Genome Research Institute (NHGRI) Web site. http://www.genome.gov/19519068. Accessed December 10, 2008.
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