A rare disease, hemophilia is a bleeding disorder in which a person's blood does not clot properly. It is caused by a defect in one of the genes that determines how the body makes certain blood-clotting factors. When clotting factors are missing (or your body does not have enough clotting factors), it can take a long time for your blood to clot after an injury or accident.
Bleeding and bruising are the major signs and symptoms of the disease. In many cases, hemophilia treatment involves injecting the low or missing clotting factors directly into the bloodstream.
(Click Hemophilia to read more about the causes, symptoms, and treatment of this inherited disease, as well as statistics on how many people are affected by it.)