A significantly increased risk for RA associated with the WDFY4 rs7097397 AG genotype was evident among female patients (OR = 1.64, 95% CI = 1.17–2.28, p = 0.004), younger patients (OR = 1.95, 95% CI = 1.29–2.94, p = 0.002), CRP-negative patients (OR = 1.56, 95% CI = 1.07–2.27, p = 0.022) and both ACPA positive patients (OR = 1.49, 95% CI = 1.03–2.16, p = 0.034) and negative patients (OR = 1.49, 95% CI = 1.03–2.16, p = 0.034) compared with the WDFY4 rs7097397 AA genotype. The gene discussed is PRTN3; the disease is rheumatoid arthritis.