Hey there not sure if anyone knows much about Gonadal Mosaic but that's what the geneticist told me I have meaning that some of my eggs have the mutation and some do not as my daughter has the deletion and is a carrier and my son has DMD he is exon deletion of 3-11. Does anyone know anything about this that can help me understand it and what would i see in my daughter (17) if she is a manifesting carrier. Thanks in advance for any help or information.
The 10-15% chance is ridiculous, as it depends on how many eggs carry the mutation. As I mentioned before there is a non-carrier mom who posted here before with 75% of her eggs carrying the mutation. Obviously, in her case, the 10-15% rule was far off. It varies from person to person. Pre-natal testing performed regardless of carrier status reduces the chance of having another son with Duchenne in many cases.
We went and saw a geneticist who told us of our chances were in having another child with DMD. As we werent a carrier the chance of it happening again was listed at about 10% through gonadal mosaiciscm. If we went PGD/IVF it would reduce the risk to 5%.
We decided the issue with IVF/PGD werent worth the reduction by 5% so we took or chances and went for it! We did have a CVS at 12 weeks, and we had a girl after 3 boys!
The 10-15% chance that is quoted in medical literature is the chance that any woman with an affected son and a negative blood carrier test would have a second affected. It is a risk based on epidemiological studies and is not referring to the percentage of eggs that could carry the DMD mutation. It is true that if a woman is a gonadal mosaic, she could have anywhere from 1% - 100% of her eggs affected. That is why prenatal testing is always offered (or should be) to any woman with an affected son.
I would also like to add that any reputable clinic should offer a less than 1 in a 1000 chance of error when performing PGD/IVF. If you are not quoted these 'odds' then I would look elsewhere.
I guess I didnt give all the information that I should have!
Yes the 10%-15% range is misleading, but it was given that you cant take it as gospel and the best way to be certain was to go with IVF/PGD as it would reduce the risk. We were also given the option of choosing to have a girl if we wanted to as it is very easy to choose a female embryo through IVF but that is for another discussion.
the only way one can be sure is to go teh IVF/PGD option or otherwise play the odds and have CVS/amnio testing, but then if you are carrying another DMD child it raises a whole new moral dilema.