Dear John
Haemophilia A is the most common bleeding disorder affecting 1 in 5.000 to 1 in 10.000 males.
It is an X-linked recessive disorder due to deficiency of coagulation factor VIII.
Clinical severity varies considerably and correlates with residual factor VIII activity.
Activity of 1% leads to severe disease that occurs in about half of affected males and may present at birth.
Activity of 1 - 5% leads to moderate disease,
Activity of 5 - 25% leads to mild disease that may not require treatment.
Affected individuals have easy bruising, prolonged bleeding from wounds, and bleeding into joints and muscles after relatively mild trauma. Repeated bleeding into joints causes a chronic inflammatory reaction leading to haemophiliac arthropathy with loss of cartilage and reduced joint mobility.
Treatment using human plasma or recombinant factor VIII controls acute episodes and is used electively for surgical procedures.
Up to 15% of treated individuals develop neutralising antibodies that reduce the efficiency of treatment.
Prior to 1984, haemophiliacs treated with blood products were exposed to the human immnodeficiency virus which resulted in a reduction in life expectancy to 49 years in 1990, compared to 70 years in 1980.
The factor VIII gene (F8C) is located on the X chromosome at Xq28 region. Mutation analysis is used effectively in carrier detection and prenatal diagnosis.
A range of mutations occur in the factor VIII gene with point mutations and inversion mutations predominating.
If you like to know which will be your risk in a future pregnancy, go inside the index web at " What happens when our recipes combine with our partner´s recipes", page 3........ clik on, disorders linked to the X-sex chromosome,........recessive:
a.- If your wife is a carrier, for the next pregancy you will be in option A .
b.- If your son will reproduce in a future, he will be C, B or D options
If you like to get more information about the disease, use the links inserted at the end of page 4, or establish contact with foundations or support organizations, you can get some of them, using the link number 8 ( Birth Defects-Genetics-Teratology-Foundations- Support Organizations) located at "links of interest".
Maite Solé
