Hemophilia B

For someone with hemophilia, injections of clotting factors are a normal part of life

Inheritance of Hemophilia B

Hemophilia B goes by many names: the Royal Disease, factor IX hemophilia, and also Christmas disease. It is the second most common cause of hemophilia, a bleeding disorder caused by a decreased ability for the body to clot. In the case of hemophilia B, the body lacks one of the molecules involved in the natural clotting reaction: factor IX. It is an X-linked condition, which is why one of the risk factors of the disease is the sheer matter of being born male. Of course, a family history is another risk, especially if it is seen on the mother's side. Women who have a family history of hemophilia may be carriers, and a carrier has a fifty percent chance of producing a hemophiliac son. It is possible for a girl to be born with hemophilia, but with all X-linked recessive conditions it is very unusual as the father would have to be affected and the mother would have to be a carrier.

The reason one of the common names for this disease is "the Royal Disease" is due to the fact that it once ran in the lines of European royalty that could be traced back to Queen Victoria. Perhaps one of the best-known of her hemophiliac descendents was Alexei, the son of Tsar Nicholas of Russia, whose bleeding was able to be helped by the monk Rasputin. He would hypnotize Alexei, and this is thought to have helped slow bleeding by calming him down. Rasputin's influences are just part of what led to the Russian revolution. It is believed all current descendents of Queen Victoria lack the gene that causes hemophilia B.

As would be expected, the main symptom of hemophilia is heavy bleeding. However, that bleeding can lead to other issues, such as joint problems and possible malformation. Other than the obvious risks that excessive bleeding can cause, there are other serious risks that can come from hemophilia. One of the common treatments in transfusions, which in the past place patients at serious risk of infectious diseases such as hepatitis and HIV. Though screening of donated blood today is very efficient and affective, there is still a risk that something may be missed. In people with a family history of the disease, genetic counseling is suggested. This is partly a preventative measure as a child born with hemophilia will have to lead a rather unusual, potentially very uncomfortable life.

Recently research into gene therapy for those with hemophilia B has produced some positive results. The current treatment of injections containing the missing clotting factor could potentially be a thing of the past. However, more research is needed before the treatment becomes widely used.

Sources are PubMed Health from the U.S. National Library of Medicine, the National Hemophilia Foundation, and the Speaking of Research Blog. Images are from Wikimedia Commons and are copyright free or under a Creative Commons license: one, two.