The genetics of type 2 diabetes

Type 2 diabetes mellitus is not a single disease but a genetically heteroge nous group of metabolic disorders sharing glucose intolerance. The precise underlying biochemical defects are unknown and almost certainly include imp airments of both insulin secretion and action. The rapidly increasing preva lence of T2D world wide makes it a major cause of morbidity and mortality. Understanding the genetic aetiology of T2D will facilitate its diagnosis, t reatment and prevention. The results of linkage and association studies to date demonstrate that, as with other common diseases, multiple genes are in volved in the susceptibility to T2D, each making a modest contribution to t he overall risk. The completion of the draft human genome sequence and a br ace of novel tools for genomic analysis promise to accelerate progress towa rds a more complete molecular description of T2D.