How is hemophilia inherited?

Hemo."A" is X-linked: Hemophilia "a" is a hereditary bleeding disorder where there is a deficiency in clotting factor viii (factor viii is needed for blood clotting). It is inherited on the x-chromosome (sex-linked). Men only have 1 "x", so if their "x" is mutated, they will have the disease. Women have 2 "x's", so they can have 1 mutated "x" and 1 normal "x", and be a carrier of the disease, with mild or no symptoms.

X chromosome: The gene that causes hemophilia a or b is located on the x chromosome, it almost always occurs in boys and is passed from mother to son through one of the mother's genes.Most women who have the defective gene are simply carriers and exhibit no signs or symptoms of hemophilia.It's also possible for hemophilia a or b to occur through spontaneous gene mutation.Hemophilia c can be passed on from eithe.