DRB3*01:01:02‐DRB1*03:01:01‐DQA1*05:01:01‐DQB1*02:01:01 (DRB3‐DR3‐DQ2.5) was the most common haplotype and occurred in 45% of CD children compared with 5% in T1D (P = 5.89 × 10−18), while DRB3*01:01:02‐DRB1*03:01:01‐DQA1*03:01:01‐DQB1*02:01:01 was the most common haplotype in T1D. Here, HLA-DRB1 is linked to type 1 diabetes mellitus.