Friday, September 2, 2005

The special testing saga

So, I discovered that there is a genetic mutation that runs in my maternal line. This is a single point mutation in a gene encoding a blood clotting protein known as Factor V (most of the clotting cascade are named in this fashion, using roman numerals). The mutation results in an aberrant form of the protein - called Factor V Leiden. This condition is autosomal dominant - to put it simply, a normal gene copy will not cancel out the bad gene. The mutant protein is harder for the body to deactivate - therefore - clotting can continue when it's not supposed to. The resulting condition is known as thrombophilia, and can be exacerbated in a person with 2 mutant genes, or mutations in other important clotting genes (such as the gene encoding prothrombin). As it happens, even if you are heterozygous for the mutation (have one copy of the mutant gene), your risks of thromboembollism are increased over the general population, and major risk factors are oral contraceptive use, surgery and pregnancy! In fact, in means your pregnancy moves from the "low risk" category to the "high risk" category. Anyhow, this condition occurs in 5% of the caucasian population in north america (and is almost non-existant in the non-caucasian population).
All this to say that I'm going to CHEO on Tuesday to have a blood test done and to meet with a genetic counsellor. Even in the worst case scenario - where I have the mutation, it is quite treatable - even during pregnancy with anticoagulants (heparin) or baby aspirin. The important thing is to know - because then, the necessary precautions (if required) can be taken to protect both Rebecca and myself. Right now, my chances of being positive are at approx. 25%.
I had to fill in a ten page family history questionnaire and fax it over to CHEO genetics labs today. It demanded a lot of detail, and I'm not sure how helpful it will be, but it allows them to build a genetic family tree for me.
Anyhow, this whole process this week (getting in touch with doctors, getting requisition, back and forth communications with CHEO, contemplating possible worst case scenarios, and assembling familial data) has been a little stressful but... I will wait and see what I find out, and work from there.
Other than that, the baby is fine, still kicking. Her favourite time of day is 10pm (for some odd reason).

1 comment:

Elizabeth Paradis said...

I know you are worried about this and I really hope that your tests are negative for Factor V. I am here if you want to talk about anything. Please say hi to Greg and pat Rebecca from me.