In particular, DRB1*04:01/02/04/05-DQA1*03:01-DQB1*03:02 and DRB1*03:01-DQA1*05:01-DQB1*02:01 haplotypes are associated with the highest T1D susceptibility whereas DRB1*15:01-DQA1*01:02-DQB1*06:02 is associated with dominant protection [3]. This evidence concerns the gene HLA-DRB1 and type 1 diabetes mellitus.