What is Klinefelter syndrome?
Klinefelter syndrome was first described by Dr. Klinefelter in 1942. It is a condition that occurs only in males. Normally, men have one X chromosome and one Y chromosome (XY). Besides the Y chromosome, men with Klinefelter syndrome have one or more extra X chromosomes (XXY, XXXY, etc.).
Men with this condition develop subtle physical characteristics that are often not visible before puberty. They usually grow tall early and display minimal physical changes during puberty such as armpit hair or beard growth.
The extra X chromosome primarily induces changes in the testicles, which produce male hormones and sperm. As a result, almost all men with Klinefelter syndrome are infertile.
Sometimes, Klinefelter syndrome can also result in delayed speech development, learning or behavioural problems during childhood or reduced ability to concentrate. In addition, other conditions that are often seen include reduced verbal skills, language problems, reduced (auditory) memory, reduced coordination skills and reduced ability for verbal expression that may lead to psychosocial problems.
Once adulthood is reached, there is a higher risk for some diseases such as brittle bones (osteoporosis), breast cancer and type 2 diabetes.