47,XXY; XXY syndrome; XXY trisomy 


Klinefelter syndrome is a chromosomal condition that affects male sexual development. Most males with Klinefelter syndrome have one extra copy of the X chromosome in each cell. Some males with the condition have low levels of the hormone testosterone beginning during puberty, which can lead to breast development (gynecomastia) and an increased risk of breast cancer, reduced facial and body hair, and an inability to father children (infertility). Boys with Klinefelter syndrome may also have di...

A genetic disorder in males caused by having an extra X chromosome. Males with this disorder may have larger than normal breasts, a lack of facial and body hair, a rounded body type, and small testicles. They may learn to speak much later than other children and may have difficulty learning to read and write. Klinefelter's syndrome increases the risk of developing testicular cancer.

Klinefelter syndrome as related to Klinefelter's Syndrome