To investigate whether the TRAF1/C5 region is associated with a specific phenotype of RA, we next stratified patients for autoantibody status from whom baseline ACPA and RF measurements were available (n = 1,814) Interestingly, SNP14/rs10818488 mainly predisposes to autoantibody-positive disease when compared to controls (OR 1.25, 95% CI 1.11–1.40, p = 2.27 × 10−4) (Figure 3A). Here, TRAF1 is linked to rheumatoid arthritis.