HLA-DRB1 and type 1 diabetes mellitus: In particular, in the present study, analysis of the genetic characteristics of T1D subjects without the classical HLA predisposing haplotypes showed that the HLA class II alleles significantly more frequent in NCH T1D subjects were part of four different haplotypes (HLA-DRB1*07:01:01-DQA1*02:01:01-DQB1*02:02:01; HLA-DRB1*08:01:01-DQA1*04:01:01-DQB1*04:02:01; HLA-DRB1*13:02:01-DQA1*01:02:02-DQB1*06:04:01; and HLA-DRB1*16:01:01-DQA1*01:02:02-DQB1*05:02:01), previously reported to have a neutral or, even, a protective role towards the T1D development risk (29, 32, 33).