I finally heard back from the genetics clinic yesterday regarding my test results for Saethre-Chotzen syndrome. Itís really fascinating and not quite what we were expecting, so forgive the length but I thought youíd be interested.
As you may know, S-C can be genetically manifested in either a mutation or a deletion in the TWIST gene. At first they did not find a mutation in my sample so they did more tests and discovered that I have a deletion. The thing is (and I read this in some journal articles as well, so I knew immediately why they were freaked out about this) a deletion usually (90% of the time) means that the person has mental retardation or other cognitive issues. But thatís not the case, and they were perplexed by this result in their labwork. So after doing some research in the literature, they think that it may be that my deletion is a small one, and that itís the larger deletions that overlap into nearby genes that may lead to mental retardation. I asked the genetic counselor if deletions can change or grow/shrink over generations, and she said no Ė that it should stay true through each generation. So it doesnít seem that there would be a risk of MR from my deletion for our kids or subsequent generations, given that itís not present in me or in any members of my family with S-C.
As far as baby-making goes, the kind of test that they did to find this deletion cannot be done in PGD. So they want to try another test (FISH), through another lab in Spokane, WA, to see if the deletion can be detected that way. If so, they could theoretically help set up a lab closer to us to do the PGD if we chose to go that route. If they canít find the deletion with FISH, then PGD may not be an option after all, although the entire clinic is still brainstorming other possibilities. The good news is that the FISH test will only take 1-2 weeks to run, once they get the sample (and right now Iím working on referrals to keep the insurance company and the genetics clinic happy so itís all done right). This first round of testing took 4 weeks to run, so this wait wonít be as long a wait.
Once these results are in, we will be speaking with plastic surgeons at the hospital experienced in cranio surgery in kids who will look over family photos to discuss what kinds of techniques they would use today to treat the kinds of cranio seen in my family thus far. We also will be talking with the OB-GYN who specializes in genetics regarding the PGD (if we can do it) and other prenatal testing options. It all seems like a lot of information, but I am glad to have it, as overwhelming as it is sometimes.
So thereís the follow-up. Iíll keep you all posted as things keep progressingÖ thanks for the support!