Hemophilia is a rare bleeding disorder that occurs when specific genes are not working properly. Those with it experiences bleeding longer after an injury because they have little or no ‘clotting factor.’ It can be acquired, however, when the body forms antibodies (proteins) that attack the clotting factor in the bloodstream. Hemophilia usually occurs in males—1 in 5,000 is born with it each year—with rare exceptions.
Hemophilia is an X-linked disorder. Since males have only one X chromosome and females have two X chromosomes, the child of a hemophiliac man and a non-carrier woman would have a 50% chance of bringing forth a female carrier or a 50% chance of a non-hemophiliac male. Each pregnancy of a carrier woman, on the other hand, has a 25% chance of resulting in a female non-carrier, a 25% chance of a female carrier, a 25% chance of a non-hemophiliac male, and a 25% chance of a male with hemophilia.
It would also be different if a woman is a carrier and the man is hemophiliac. Her pregnancy will have a 25% chance to blossom to a female carrier, a 25% chance of a female with hemophilia, a 25% chance of a non-hemophiliac male, and a 25% chance of a male with hemophilia.
Both hemophiliac parents could have a 50% chance of having a hemophiliac daughter or a 50% chance of a hemophiliac son. A hemophiliac woman that copulated with a non-hemophiliac man has a 50% chance of delivering a female carrier or a 50% chance of a male with hemophilia.
There are drugs nowadays that could be injected thrice a week to help a hemophiliac’s blood clot. A dose costs $2,500 and could prevent cuts and internal bleeds from seeping into joints and organs. There’s also a kind of gene therapy being developed by the Baxter International Inc. that could clot blood for—if not for life—a number of years.
Aside from Baxter, there’s also the Uniqure that just started its trial; Dimension Therapeutics that has partnered with Baxter; Spark Therapeutics that originated from The Children’s Hospital of Philadelphia; Biomarin Pharmaceutical; Sangamo Biosciences/shrine; and Biogen Idec. The ‘benefit would be a long time coming,’ though, as the xconomy put it.
“Until the 1980s, hemophiliacs who bled were rushed to the hospital and infused with a concentrated form of the ‘clotting factor’ or protein that their bodies don’t produce.”
Last March 15, researchers led by Dr. Valder R. Arruda from The Children’s Hospital of Philadelphia have identified FIX-Padua, a mutant human protein that has been able to relieve symptoms of hemophilia in three dogs with severe forms of the disease. It could clot blood 8-12 times stronger than the normal factor IX (FIX) gene, which could eventually provide a new approach to gene therapy not only for hemophilia but for other genetic diseases that inhibit antibodies as well.
“When you belong to a disease group that is as small as hemophilia, it’s best that you provide some example that you exist, and that you’re living a full life.” ~Val Bias
Video taken from the YouTube Channel of the NHS Choices