HLA-DRB1 and type 1 diabetes mellitus: Risk can be independently conferred by DQ and DR alleles: for instance, type 1 diabetes risk is independently associated with both DQ2.5/8 alleles (HLA-DQB1*0201/HLA-DQB1*0302) and DR3/4 alleles (HLA-DRB1*0301/ HLA-DRB1*0405, HLA-DRB1*0401) (23).