I don't think it has anything to do with genetics or race. It has to do with what's being put in the mouth. No matter where someone is from.
I had a guy recently tell me that he has diabeties on both sides of his family. He has learned about low carb and we were talking about it. Then he told me about going through MDonalds and buying his dog his own burger. Now we know nothing good happens in the MD drive through. He's a 100 lbs over weight. He comes from a family who is eating tons of carbs. If it's rice, chips, fries, crackers, bread, cereal, it ALL turns to sugar in the body.