Three DRB1~DQB1 haplotypes were strongly associated with T1D: DRB1⁣∗03:01:01~DQB1⁣∗02:01:01, DRB1⁣∗09:01:02~DQB1⁣∗02:02:01, both predisposing, and DRB1⁣∗15:03:01~DQB1⁣∗06:02:01, protective. This evidence concerns the gene HLA-DRB1 and type 1 diabetes mellitus.