In insulin-dependent diabetes mellitus, HLA-DR markers are involved, namely DR3, DR4 and DR9 alleles, among black senegalese populations. Studying the different associations of these alleles showed a strong predisposition to insulin-dependent diabetes mellitus with DR3/4 (p > 10(-2); OR = 13.6); DR4/9 (p < 10(-2); OR = 8.32) and DR9/9 (p < 0.05; OR = 7.78). And then it was observed a tendency to an inverse relationship of DR3/4 frequency with age of onset in male patients.