46 JISHIM 2009-2010, 8-9 Introduction The history of haemophilia represents one of the human mind attempts to define and encompass a mysterious fascinating phenomenon. Although some western historians claimed the priority of discovering this phenomenon to Jewish writings or recent physicians, the real priority may be attributed to Albucasis, the Arabian physician who died in the 11 th century. Treatment options for hemophilia patients present one of the most stimulating treatment stories of any patient group with an inherited disorder. Definition Haemophilia is derived from the Greek “haima” which means blood and “philia” which means friend. In Arabic language; haemophilia means Naaor (ﺭﻭﻉﺍﻥ) which means the unstopped bleeding vessel. Haemophilia (also spelled Hemophilia in North America) is conventionally a group of hereditary genetic disorders that impair the body’s ability to control blood clotting or coagulation. Thus, prolonged bleeding and re-bleeding are the diagnostic symptoms of haemophilia, especially haemarthrosis, haematuria and large bruises. The most common form of haemophilia is haemophilia A which is an X-linked recessive inherited bleeding disorder resulting from a mutation in the F8C gene which results in a deficiency of factor VIII. About a third of mutations are new sporadic mutations. Whereas, haemophilia B is an X-linked recessive inherited bleeding disorder, previously known as Christmas disease, resulting from a mutation in the F9 gene which causes a deficiency of factor IX. Similarly to most recessive sex-linked, X chromosome disorders, only males typically exhibit symptoms. Because females have two X chromosomes and because haemophilia is rare, the chance of a female having two defective copies of the gene is very low, thus females are almost exclusively a symptomatic carriers of the disorder. Bleeding manifestation in hemophiliac individuals are related to the level of reduced factor. There are other rare forms of haemophilia, which are less important. Hemophilia in the Ancient and Medieval Ages The genetic mutation originally responsible for haemophilia in mammals is generally considered to be many thousands of years old. The study of blood coagulation can be traced back to about 400 BC and the father of medicine, Hippocrates. He observed that the blood of a wounded soldier congealed as it cooled. Additionally, he noticed that bleeding from a small wound stopped as skin covered the blood. If the skin was removed, bleeding started again. Aristotle noted that blood cooled when removed from the body and that cooled blood initiated decay resulting in the congealing of the blood. Who Discovered Hemophilia? Abdul Nasser Kaadan MD, PhD * , Mahmud Angrini MD ** * Chairman, History of Medicine Department, Aleppo University, Aleppo-Syria. The President of ISHIM (www.ishim.net) e-mail: a.kaadan@scs-net.org ** Master Student, History of Medicine Department, Aleppo University, Aleppo-Syria. Master Degree in Laboratory Medicine e-mail: dr-ma@aloola.sy Summary In the whole history of hemophilia, it is generally accepted that the main development in understanding the cause and the inheritance type of the disease accomplished in the last century. But, who really was the first to describe the disease? The priority of the disease is still a matter of argument. We followed the tracks of hemophilia in history since the ancient times to the recent, trying to identify the priority in each discovery related to the disease, chasing the advances in treatment. We found that the Arabian physician Albucasis may be the first who described the disease. He defined the disease, witnessed some cases, named it, and even suggested a treatment. Then, more than seven centuries had passed until the concern about the disease revived, thanks to its spread in the royal families of Europe. In our treatise, we tried to shed light on the most important events in the history of hemophilia. We clarified how hemophilia spread in the royal families through Europe. Finally, we mentioned the discoveries and inventions in the recent age. Keywords: History of Hemophilia, Clotting Factors, History of Medicine, Albucasis, John Conrad Otto, Queen Victoria.