One theory is that humans of certain ethnicities aren't equipped to digest certain carbohydrate types. (supernaturalacnetreatment.com)
These variants are often found primarily in certain ethnicities. (23andme.com)
Actually, type I diabetes is associated with genetic predisposition, specifically it is common with certain tissue types (which makes sense, as it is an autoimmune disorder), and also certain ethnicities, and is highly heritable. (skepticalob.com)