Blood Coagulation Factor VIII (Hemophilia A)

Hemophilia was the first major disease recognized
to be genetically determined. The Talmud
refers to its increased occurrence in males in
certain families, corresponding with X-chromosomal
inheritance. Hemophilia A results from
the deficiency of blood coagulation factor VIII;
hemophilia B results from a deficiency of factor
IX. Factor VIII functions as a cofactor in the activation
of factor X to factor Xa during the intermediate
phase of the coagulation cascade.