Hi Katie

Diane is correct: it is most likely that one of your parents is a carrier. However I believe it is technically possible that neither or indeed both are carriers.

Lynn T, I believe you too are correct when you say that most cases fit the pattern. I just notice that your geneticist is saying that not all of them do, even if you count out germline mutations. We've met a heterozygous sufferer, so they can't be that rare. The 1998 Mexican study seemed to indicate that there are different genetic mechanisms causing CAH in many cases (19% of families in this study).

This is a difficult subject to approach from a non-medical backgound, so if anyone has more information, I'd be most interested.

Andrew