HLA-DRB1 and type 1 diabetes mellitus: Association analysis of the imputed HLA variants with T1D identified the most significant association at the HLA-DRβ1 amino acid position 71 (Pomnibus = 7.5 × 10−120; Fig. 5a and Supplementary Data 1), one of the T1D risk-associated amino acid polymorphisms in the European population12.