HLA-DRB1 and type 1 diabetes mellitus: The top candidates within the HLA locus were HLA-DQB1 and HLA-DRB1, which together form the haplotype DR4—one of two haplotypes with the strongest association with T1D (Figs 4B and S7A).[34] These genes are strongly connected by chromatin folding associated with all types of investigated regulatory elements containing one or more T1D-associated genetic variants (Figs 4C and S7B).