Hi!

I am no expert, but when my son was born(SWCAH) 10 years ago, we were told that 1 in about 14,000 have it (in general, not in NA in particular).  We were also told that about 1/50 or 1/60 in the general population are carriers of the gene.

I haven’t been able to find my notes, but I also believe that certain ethnic groups have higher rates - I seem to remember them asking us if we had any Eskimo or certain type of Jewish heritage.  Sorry for the lack of true, hard facts, but I hope this gives you some idea.