GADA-negative patients demonstrated an association with HLA-DRB1*04 and protection with HLA-DRB1*15. In short, they have some of the immunogenic features of the autoimmune diabetes of adolescent and adult European-origin and Chinese populations [41], while the diabetes-associated autoantibody, GADA, was similarly the dominant autoantibody and associated with HLA-DRB1*03:01, consistent with heterogeneity of type 1 diabetes endotypes [42, 43]. This evidence concerns the gene HLA-DRB1 and type 1 diabetes mellitus.