Polymorphism of the HLA-DQA1 and DQB1 genes in healthy muscovites and patients with diabetes mellitus types 1 and 2

The polymorphism of HLA-DQA1 and DQB1 genes was studied in healthy individu als (N = 121) and in patients with diabetes mellitus type 1 (IDDM, N = 113) or type 2 (NIDDM, N = 99) from Moscow. The DQA1 alleles coding for Arg-52 in chain DQ alpha and the DQB1 alleles coding for all but one (Asp) amino a cids in position 57 (non-Asp-57) of chain DQ beta proved predisposing to ID DM and NIDDM (alleles S). The alleles for non-Arg-52 in DQ alpha and for As p-57 in DQ beta were associated with lower risk of DM. The risk increased w ith the increased number of alleles S in DQA1/DQB1, being maximum in homozy gotes SS/SS. The association of the HLA-DQ locus with IDDM was more signifi cant than with NIDDM.