Hate to say it, but B.S. it isn't. Diabetes is a threshold disease, involving both genes and environmental factors. A combination of them can put you into the threshold or keep you out. This is in contrast to diseases like CF where you either are or aren't. Sorry your answer is so difficult to get at Tom. Folks aren't airplanes, and don't act like them. Folks are complicated, and often poorly described in numeric terms.