There are many different types of bleeding disorders, hemophilia A (factor VIII deficiency), hemophilia B (factor IX deficiency), von Willebrand disease, and rare factor deficiencies including I, II, V, VII, X, XI, XII and XIII.
Hemophilia A
Hemophilia A, also called factor VIII (FVIII) deficiency or classic hemophilia, is a genetic disorder caused by missing or defective factor VIII, a clotting protein. Although it is passed down from parents to children, about 1/3 of cases are caused by a spontaneous mutation, a change in a gene.
According to the US Centers for Disease Control and Prevention, hemophilia occurs in approximately 1 in 5,000 live births. There are about 20,000 people with hemophilia in the US. All races and ethnic groups are affected. Hemophilia A is four times as common as hemophilia B while more than half of patients with hemophilia A have the severe form of hemophilia.
Hemophilia B
Hemophilia B, also called factor IX (FIX) deficiency or Christmas disease, is a genetic disorder caused by missing or defective factor IX, a clotting protein. Although it is passed down from parents to children, about 1/3 of cases are caused by a spontaneous mutation, a change in a gene.
According to the US Centers for Disease Control and Prevention, hemophilia occurs in approximately 1 in 5,000 live births. There are about 20,000 people with hemophilia in the US. All races and ethnic groups are affected. Hemophilia B is four times less common than hemophilia A.
Von Willebrand Disease
Von Willebrand disease (VWD) is a genetic disorder caused by missing or defective von Willebrand factor (VWF), a clotting protein. VWF binds factor VIII, a key clotting protein, and platelets in blood vessel walls, which help form a platelet plug during the clotting process. The condition is named after Finnish physician Erik von Willebrand, a who first described it in the 1920s.
VWD is the most common bleeding disorder, affecting up to 1% of the US population. It is carried on chromosome 12 and occurs equally in men and women.
Other Factor Deficiencies
In the US, a rare disease or disorder is defined as one that affects fewer than 200,000 people, making hemophilia A and B, and still less prevalent factor deficiencies such as I, II, V, VII, X, XI, XII and XIII, rare disorders. These very rare factor deficiencies, from factor XIII deficiency, the rarest, occurring in an estimated 1 out of 5 million people, to factor XI deficiency, occurring in about 1 out of 100,000, were all discovered and identified in the 20th century. The majority of these conditions were only identified within the last 60-70 years. Here you will find information on how factor deficiencies I, II, V, VII, X, XI, XII and XIII are inherited identified and managed.