Hemophilia A and B are X-linked chromosome bleeding disorders and they are caused by mutations in factor VIII (FVIII) and factor IX (FIX) genes. Hemophilia A and B are considered rare diseases, which occur in one per 5000 births and one per 50.000 male births.

The hallmark of hemophilia is hemorrhage (bleeding) into the joints. The bleeding is painful and leads to long-term inflammation and deterioration of the joint. In the absence of intervention, the patient with prolonged symptoms will suffer permanent deformities, misalignment, and loss of mobility.

Typically, hemophilia is diagnosed before or right after birth. In case no family history of hemophilia exists, the disease is only diagnosed when the child begins to crawl or walk. Genetic and blood tests can confirm if hemophilia is suspected. In particular, the amount of factor VIII and IX in the blood is measured. In addition, blood clotting tests give additional information for the diagnosis. The complete blood count of people with hemophilia is in the normal range, and no abnormalities of blood cell morphology can be detected microscopically.

Hemophilia B treatment is using Factor IX.