In T1D w/CD, being homozygous for DRB4*01:03:01‐DRB1*04:01:01‐DQA1*05:01:01‐DQB1*03:02:01 (DR4‐DQ8/DR4‐DQ8) was the most frequent genotype and found in 42% (OR = 21.67; 95% CI (2.68, 158.4), P = 0.002) compared with 3.2% in CD and 10% in T1D (OR = 6.28; 95% CI (0.76, 46.47), P = 0.04, Data not shown) children, respectively. Here, HLA-DRB1 is linked to type 1 diabetes mellitus.