HLA-DRB1 and type 1 diabetes mellitus: In our cohort, most children with T1D carried known susceptibility alleles, specifically HLA-DR3-DQ2 (haplotype HLA-DRB1 03:01–DQA1 05:01–DQB1 02:01) and/or HLA-DR4-DQ8 (HLA-DRB1 04:01–DQA1 03:01–DQB1 03:02)1, while healthy donors reflected the general HLA distribution in the Czech population55 (Supplementary Fig. 15A).