A GENOME-WIDE SEARCH FOR HUMAN NON-INSULIN-DEPENDENT (TYPE-2) DIABETES GENES REVEALS A MAJOR SUSCEPTIBILITY LOCUS ON CHROMOSOME-2

Non-insulin-dependent (type 2) diabetes mellitus (NIDDM) is a common d isorder of middle-aged individuals characterized by high blood glucose levels which, if untreated, can cause serious medical complications a nd lead to early death. Genetic factor splay an important role in dete rmining susceptibility to this disorder. However, the number of genes involved, their chromosomal location and the magnitude of their effect on NIDDM susceptibility are unknown. We have screened the human genom e for susceptibility genes for NIDDM using non- and quasi-parametric l inkage analysis methods in a group of Mexican American affected sib pa irs. One marker, D2S125, showed significant evidence of linkage to NID DM and appears to be a major factor affecting the development of diabe tes mellitus in Mexican Americans. We propose that this locus be desig nated NIDDM1.