Gene Location

Hemophilia is caused by a defect in the genes that determine how the body makes blood clotting factors. The gene is located on the X chromosome only. Which is why the disease is usually found in men only. Females need both of their X chromosomes to be affected before they can have hemophilia. This is very rare, because men have only one X chromosome it is far more easier for men to inhereit the disease.

Inheritance chart #1

Inheritance chart #2