HLA-DPB1 and rheumatoid arthritis: The OR for DPB1*02:01 in ACPA(+)RA patients with DRB1*04:05 was 1.45 (P = 0.0688, S2 Table), while the OR for DPB1*02:01 in ACPA(+)RA patients without DRB1*04:05 was 1.26 (P = 0.0356, S2 Table).