Like celiac disease, Type I diabetes is more common in those of northern European extraction. Like celiac disease, it is highly linked to the so-called HLA markers of the immune system, those marking white blood cells. Celiacs are likely to be positive for both HLA-B8 and HLA-DR3; Type Is are most linked to HLA-B8 and either HLA-DR3 or HLA-DR4. An English study about 6 months ago found that multiple genes were linked to Type I reflecting the fact that parents of a Type I are often diabetes free: the interpretation being that genes were required from both sides. The recent request for celiac siblings for a study of genetic typing intends to duplicate that one looking for celiac genes.
References: Gluten Intolerance Group of North America newsletter, V. 13, Issue 2, 1987; New York Times, Sept. 13, 1994, genetics study by Dr. John Todd at Oxford, summarized by Kemp Randolph.
For more information see our Related Disorders page.