The most prominent genetic risk factors are alleles within the HLA class, particularly HLA-DRB1 [29], while a large number of non-HLA genes (FLT3, IRF5, STA4) involved in autoimmune diseases are interlinked in a network that regulates IFN signalling and dendritic cell and T cell function [30, 31]. This evidence concerns the gene HLA-DRB1 and autoimmune disease.