But genetic predisposition to diabetes is far from the whole story. For one thing there is a high prevalence of these so-called susceptibility genes in the general population, yet this is not reflected in the incidence of the disease. Even in identical twins, one of which may develop diabetes, in about half the cases the other twin, who carries the same genes, does not develop diabetes. At the end of their two-day meeting Thomas Merigan, MD, Stanford University Medical Center, Stanford, CA, drew up a short list of suggestions that emerged from the discussions. There is a need for a US survey to identify those at high risk of diabetes by evaluating genetic markers and measuring autoantibodies as well as to make a major effort to obtain pancreatic tissues from persons who die of diabetes.
More emphasis is needed on the epidemiology of diabetes.
There are a whole set of questions that need to be answered regarding studies on environmental factors, migrant populations and indeed the entire natural history of the disease. The epidemiology of the disease has to be in place in order to deal adequately with any good idea about controlling the disease, Merigan said. The possibility of doing intervention trials involving modification of diets, the use of antiviral agents, or immunosuppressive measures, should be explored. Dietary factors and infectious agents have been implicated in the development of diabetes, but definitive proof is still lacking. There is a need to study relevant animal models and tissue culture systems so as to look at the production of disease, at interactions between the islet cells of the pancreas and immune system mechanisms.