Forty-three RCTs reported RA and showed that IGU + MTX therapy can improve ACR20 (RR 1.45 [1.14, 1.84], <i>p</i> = 0.003), ACR50 (RR 1.80 [1.43, 2.26], <i>p</i> < 0.0000), ACR70 (RR 1.84 [1.27, 2.67], <i>p</i> = 0.001), DAS28 (WMD -1.11 [-1.69, -0.52], <i>p</i> = 0.0002), reduce ESR (WMD -11.05 [-14.58, -7.51], <i>p</i> < 0.00001), CRP (SMD -1.52 [-2.02, -1.02], <i>p</i> < 0.00001), RF (SMD -1.65 [-2.48, -0.82], <i>p</i> < 0.0001), and have a lower incidence of adverse events (RR 0.84 [0.78, 0.91], <i>p</i> < 0.00001) than the control group. The gene discussed is CRP; the disease is rheumatoid arthritis.