HLA-DRB1 and type 1 diabetes mellitus: For instance, specific interactions that increase T1D disease risk were described between HLA-DRB1*03:01-DQB1*02:01/DRB1*04:01-DQB1*03:02 genotypes [49] and for several combinations of the common HLA-DRB1, HLA-DQA1, and HLA-DQB1 haplotypes [43].