Klinefelter syndrome

Klinefelter's syndrome is a set of symptoms resulting from two or more X chromosomes in males. The primary feature is sterility. Symptoms are often subtle, and many people do not realize they are affected. Sometimes symptoms are more prominent and may include weaker muscles, greater height, poor coordination, less body hair, smaller genitals, breast growth, and less interest in sex. Symptoms are typically more severe if three or more X chromosomes are present.