Genetic epidemiology of insulin-dependent diabetes mellitus: international comparisons using molecular genetics

International comparative molecular studies of insulin-dependent diabetes mellitus can be viewed from an immunogenetical and an epidemiological perspective. Each approach independently contributes to our knowledge concerning the etiology and prevention of the disease. However, the combination of these perspectives, representing an interface between molecular biology and epidemiology, will achieve more in terms of scientific advancement and public health than either perspective alone. An excellent example of the development of molecular epidemiology has been the evolution of international comparative research through the WHO Multinational Project for Childhood Diabetes. Case-control molecular studies are currently being conducted to test the hypothesis that population variation in the frequency of HLA class II susceptibility alleles is the primary determinant of the global patterns of insulin-dependent diabetes mellitus incidence. Preliminary data suggest that this hypothesis is correct. Future international molecular epidemiological studies, encompassing host-environment interactions, will lead to a better understanding of the relationships among specific risk factors within populations and across the world. Molecular epidemiology represents a new paradigm for studying the etiology and epidemiology of infectious and non-communicable diseases, and no doubt represents a major challenge for the 1990s.