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Male With Klinefelter Syndrome

Male with Klinefelter syndrome

Klinefelter syndrome is a genetic condition that affects males. Klinefelter syndrome occurs when a boy is born with one or more extra X chromosomes. Most males have one Y and one X chromosome. Having extra X chromosomes can cause a male to have some physical traits that are unusual for males.

Many men with Klinefelter syndrome do not have obvious symptoms. Others have sparse body hair, enlarged breasts, and wide hips. In almost all men, the testicles remain small. In some men, the penis does not reach adult size.

Current as of: March 3, 2021

Author: Healthwise Staff
Medical Review:
John Pope MD - Pediatrics
Martin J. Gabica MD - Family Medicine
Adam Husney MD - Family Medicine
Siobhan M. Dolan MD, MPH - Reproductive Genetics

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