HLA-A, B, DR antigens and insulin-dependent diabetes in Algerians.

HLA-A, B and DR antigens have been investigated in insulin-dependent diabetics and compared to controls in a population of Algerians. A decrease of A1 and DR2 and an increase of Aw 19.2; B8, B18 and especially DR3 were found in diabetics in comparison to controls. The strongest association was found for DR3, which is a good genetic marker of IDD (RR = 8.50) in this population. The frequency of some HLA antigen associations in IDD suggests that the diabetic gene(s) is linked to 2 main haplotypes: Aw 19.2; B18; DR3 and Aw 19.2; B8; DR3. Antigen DR4 was equally represented in IDD (21%) and controls (28.4%), but heterozygote DR3-DR4 was more frequent in diabetics. The relation between IDD and HLA antigens found in the Algerian population is very similar to that described in diabetic Caucasian populations of southern Europe, except for the lack of association with DR4.