HLA-DRB1 and autoimmune disease: We found that the susceptibility alleles, HLA-DRB1*08:02 and DPB1*05:01, increased the frequencies of concomitant autoimmune diseases and autoantibodies such as Sjögren syndrome and anti-SS-A/SS-B antibodies, while the resistance allele, DRB1*09:01, was also associated with increased frequencies of co-existing autoimmune diseases, such as Sjögren syndrome.