What Causes Klinefelter Syndrome?

Klinefelter syndrome is a genetic disorder in which a boy is born with an extra copy of the X chromosome. Men with Klinefelter syndrome have XXY chromosome in their cells instead of XY chromosome. Low muscle tone, low testosterone, small testicles, large breast tissues, mild dyslexia, etc. are some of the symptoms of this sex chromosomal disorder. Many men who have this disorder do not realize it until adulthood when they face issues due to infertility.

In this article, we will discuss what causes Klinefelter syndrome.

Klinefelter Syndrome Causes

An extra copy of X chromosome can occur due to nondisjunction of sex chromosomes. Every individual has 46 chromosomes that include two sex chromosomes, X and Y. Men have one X and one Y chromosome. Men inherit the X chromosome from their mother and the Y chromosome from their father. In the case of KIinefelter, men inherit an extra X chromosome from either of the parents.

This is thought to be caused due to the failure of chromosome separation or nondisjunction during the egg or sperm formation in the parent. If the gamete with the extra X chromosome happens to fuse with the normal gamete, then the embryo may inherit this extra sex chromosome. Women who conceive after the age of 35 have higher chances of having a boy with this rare genetic disorder.

Some men have this extra copy of the X chromosome in each cell of their body. While others have it in some of their cells, which is known as the mosaic Klinefelter syndrome.