HLA-DRB1 and type 1 diabetes mellitus: By 2015, Hu and colleagues also identified 3 amino acid positions (HLA-DQβ1 position 57, HLA-DRβ1 positions 13 and 71), accounting for 90% of HLA class II phenotypic variance responsible for presenting antigenic peptides that activate autoreactive T cells and drive significant hereditary T1D risk (Hu et al, 2015).