HLA-DRB1 and autoimmune disease: In three genome-wide association studies (GWAS) so far, the first of them revealed the impact of the polymorphisms in the HLA-DQA1 and HLA-DQB1 intergenic zone and at the HLA-DRB1 locus (HLA-DRB1*11 and DRB1*13), and, more importantly, the second determined that the haplotype HLA-DRB1*01:01~DQB1*05:01~DQA1*01:01 was only associated with susceptibility to IgAV but not with other autoimmune diseases, highlighting that IgAV is a prototype of HLA class II disease.