HLA-DRB1 and rheumatoid arthritis: Conversely, the frequencies of HLA-DRB1*07:01:01, *14:01:01, *15:01:01:01 and HLA-B*15:01:01, *15:02:01, and *38:02:01 alleles were decreased in RA group (OR < 1, all P < 0.05).