No increased risk of ACPA-negative RA was found in individuals carrying any SE allele (OR = 1.2; 95% CI, 0.8 to 1.7), or the HLA-DRB1*04:05 allele when this was investigated separately (OR = 1.2; 95% CI, 0.8 to 1.9). Here, HLA-DRB1 is linked to rheumatoid arthritis.