Regarding the genotype and allele frequencies of NCF4 rs1883112, rs4821544, and rs729749, we noted that the CT genotype and C allele frequencies of rs4821544 in RA patients were significantly decreased when compared to controls (CT vs. TT: OR = 0.752, 95% CI: 0.571-0.991, P = 0.043; C vs. T: OR = 1.316, 95% CI: 1.026-1.688, P = 0.031). This evidence concerns the gene NCF4 and rheumatoid arthritis.