The term haemophilia covers a number of clinical conditions in which a tendency to bleed occurs to varying degrees due to disorders of haemostasis. The first written record of haemophilia is found in the Jewish Talmud (5th century after). There it states:
"If two boys die from bleeding at their circumcision, all other sons of the mother, of her daughters and of her sisters do not need to be circumcised."
This observation indicated that the tendency to haemorrhage is a hereditary phenomenon, and that it is passed on primarily on the mother’s side. In 1803 the American physician Otto described the phenomenon of bleeders for the first time and reported that it was a hereditary bleeding disease which primarily affects male offspring and is transmitted on the mother’s side. In the 1940s the Argentinian Pavlovsky discovered that the bleeding defect of a haemophiliac could be corrected by a blood transfusion from another haemophiliac. It was another 10 years before two different forms of haemophilia were discovered, which were designated haemophilia A and B.
These two most commonly occurring types of haemophilia are characterised by the fact that hereditary changes (mutations) in the genes for factor VIII (haemophilia A) or factor IX (haemophilia B) result in a functional impairment or complete absence of the corresponding proteins active in coagulation. These two factors were described for the first time in 1947 (factor VIII) and 1952 (factor IX).