Cindy, The quick answer to your question is that although it is possible for a person to have genes for two different forms of CAH, the person would be a carrier for both forms of CAH but wouldn't actually have either form of CAH. A person must have two copies of the genes for exactly the same type of CAH before he or she will have CAH. The odds are astronomically high against a person having two defective sets of genes for two different forms of CAH. Now the long answer. Everything known to date shows that all forms of CAH are carried by recessive genes. Genes are DNA sequences that give the body instructions for making proteins. Enzymes are a type of protein that perform many critical functions in the body. In all cases of CAH there is a defect in one of the enzymes needed to manufacture cortisol. A simple explanation for why CAH is called recessive is this. We have two copies of every type of gene. One copy came from our father and the other from our mother. Most people get normal copies of all of the genes for all cortisol enzymes from both parents. Occasionally a person will get a normal copy of the gene responsible for a particular cortisol enzyme from one parent and a defective copy of the gene for the same enzyme from the other parent. This does not cause the person to have CAH because the normal gene allows a functioning enzyme to be made. The normal gene is said to be dominant over the defective (CAH) type gene since it masks the effect of the defective CAH gene. The CAH type of cortisol gene is called recessive because of this masking effect. Such a person with one normal cortisol gene and one CAH type of cortisol gene is said to be a CAH carrier. If two CAH carriers with the same type of defective gene (same enzyme defect) have a child there is a one in four (25%) chance the child will get a defective gene for making that enzyme from both parents and end up with CAH. There is also a one in four chance that the child will receive a normal copy of the gene from both parents not even be a CAH carrier. The greatest likihood, one out of two or 50%, is that the child will get a normal gene and a CAH gene. In that case the normal gene will produce the functional cortisol enzyme and the child will not have CAH but will be a carrier of CAH. I have tried to illustrate the situation when both parents are carriers of the same form of CAH with the box below. The N stands for a Normal gene and the C stands for a gene that codes for a defective (CAH) form of the cortisol enzyme. The N C across the top stands for the genetic makep of one parent and the N C down the left side stands for the genetic makeup of the other parent. The middle four combinations are the possible gene combinations that any of their children could receive from the parents. ____N____C_ N | (CN) (CC) C | (NN) (NC) Only the CC combination will result in CAH. Either the (NC) or the (CN) combination will result in the child being a carrier without having CAH, just like the parents. The (NN) combination is completely normal and does not even carry CAH. I hope this helps somewhat and wasn't too confusing. Joan