[Genetics of diabetes mellitus].

Diabetes is genetically heterogeneous. The subdivision of idiopathic diabetes should better be performed according to the necessity of treatment (dependence on insulin) than according to the age in the primary manifestation. Up to now only few genetic entities are clinically defined, and a coordination to certain types is often difficult in the individual case. Altogether the genetic load is clearly smaller in the insulin-dependent diabetes. The risk for children of insulin-dependent diabetics is only about 1-2%. Since the risk of disease for children of young non-insulin-dependent diabetics is about 50%, a clear clinical diagnostics of the mothers within the consultation is important. However, there are no reliable genetic markers for an exact subdivision into types in the individual case. The association of certain HLA-types with insulin-dependent diabetes is theoretically of great interest and refers to the participation of autoimmunological phenomena in the development of this type of diabetes. However, the estimation of HLA is not helpful for the consideration of individual cases, also within a genetic consultation. the existing heterogenias within the non-insulin-dependent diabetes are not yet sufficiently clarified. This type is altogether much more genetically determined, particularly when it appears in younger age and when it is not associated with adiposity.