Hemophilia

toc ** Hemophilia ** By Jared Linsky and Alexi Themelis

What is Hemophilia?
Hemophilia is an inherited bleeding disorder in which your blood clotting process is delayed.(5) Blood clotting is important because it stops bleeding after you get a cut, which in turn forms a scab. In regular blood clotting, there are at least foruteen steps requiring a specific protein in the blood. In someone with hemophilia, one or more of the protiens needed for those fourteen steps is deficient or missing. In someone with hemophilia, excessive bleeding occurs after cuts, and excessive internal bleeding can occur after bruises.(6) There are two different forms of Hemophilia: hemophilia A and hemophilia B. Hemophilia A is a deficiency of factor VIII (Eight), and hemophilia B is caused by a deficiency of factor IX (Nine). (4)

Click here to see a video on hemophilia http://www.youtube.com/watch?v=OeT2cxgmxF0

How common is Hemophilia?
First of all, hemophilia is more common in males than in females, because a male needs only one hemophilia gene, while a female needs two. If a female has one hemophilia gene, then she is a carrier. approxamitely one in every ten-thousand males has Hemophilia A, and one in five-thousand females is a carrier for Hemophilia A. About one in every forty-thousand males has Hemophilia B, and one in every twenty thousand females is a carrier for Hemophilia B .(5) About 9 out of 10 people who have hemophilia have type A. About 7 out of 10 people who have type A have the severe form of it. (1)

What are the Symptoms of Hemophilia?
The main symptoms of Hemophilia are both internal and external bleeding anywear, but mainly on the elbows (above), knees (also above), wrists. There are three different severety factors of hemophilia: severe, moderate, and mild. Depending on the severity of the diesease, symptoms may be more or less severe.(5) There may also be bleeding in the muscles, and in the digestive track. Other symptoms include prolonged nosebleeds, excessive bleeding from biting down on lips, excessive bleeding following tooth extraction, excessive bleeding following surgery, and blood in the urine. (2)

What is the Pattern of Inheritance for Hemophilia?
Hemophilia is a sex linked recessive gene on the "X" Chromosome, which means if there is one of the Hemophilia genes in a female, she is a carrier, and if she has two Hemophilia genes, she has Hemophilia. On the other hand, a male needs only one Hemophilia gene to have Hemophilia.. The reason it is so common in males is because males have only one "X" chromosome. A female's sex cell is XX, and the male sex cell is XY. Say the letter H represents a gene with hemophilia, and the letter h represents someone without hemophilia. If a female is XhXh, and a male is XhY, then there is no possibility that a child will get hemophilia. If a female is a carrier for Hemophilia, and a male does not have hemophilia, there is a 50% chance that a female will be a carrier, and a 50% chance that a male will have Hemophilia. If a female has Hemphilia and a male doesn't have Hemophilia, then the chances of having a boy with hemophili is 100%, and the chances of having a daughter who is a carrier is 100% If a female doesn't have hemophilia, but a male does, the chances of having a boy with hemophilia is 0%, and the chances of having a girl carrier is 100% If a female is a carrier, and a male has Hemophilia, then the chances of having a boy with hemophilia is 50%, and the chances of having a female with hemophilia is 50%, and the chances of having a female carrier is 50% If both parents have Hemophilia, then there is a 100% chance that all of the children will get Hemophilia (1)
 * Parents || Xh || Y ||
 * Xh || XhXh || XhY ||
 * Xh || XhXh || XhY ||
 * Parents || Xh || Y ||
 * XH || XHXh || XHY ||
 * Xh || XhXh || XhY ||
 * Parents || Xh || Y ||
 * XH || XhXH || XHY ||
 * XH || XHXh || XHY ||
 * Parents || XH || Y ||
 * Xh || XhXH || XhY ||
 * Xh || XHXh || XhY ||
 * Parents || XH || Y ||
 * XH || XHXH || XHY ||
 * Xh || XHXh || XhY ||
 * Parents || XH || Y ||
 * XH || XHXH || XHY ||
 * XH || XHXH || XHY ||

Diagnosis
To diagnose Hemophilia, a series of blood tests have to be taken and examined to see if clotting factors are missing or defient. Pregnant women can get testing done in early pregnancy to make preperations if the child is predicted to have the disease. Most of the predictions are correct, although sometimes a child can be predicted to have Hemophilia, and ends up fine, or vice versa. (3)

Treatments
An FDA approved method of Hemophilia treatment is to insert the missing blood proteins (clotting factors) which is done by injecting it into the bloodstream. (1)

Fun Facts
People who don't have hemophilia have a factor VIII activity of 100%. People who have severe hemophilia A have a factor VIII activity of >1%.(2)