We sent in blood samples from my husband, my CAH son, and myself. My son and I had the standard mutation, my husband they could not find a mutationn, they said if they were testing him alone they would have said he would not be a carrier, we know he is a carrier because both of our kids have CAH, anyway it is an interesting and not an excact science. When I talked to Cornell they kind of asked me if my husband was the father, funny as my boys look exactly like their Dad.
Good Luck.