In the overall analysis, significantly decreased association could be observed between RA risk and the variant genotypes of IL-21 rs6822844 in three different genetic models from whole populations: in the allelic contrast (OR = 0.77, 95% CI = 0.62–0.97, Pheterogeneity<0.001, P=0.024, Figure 3), the heterozygote comparison (OR = 0.68, 95% CI = 0.50–0.92, Pheterogeneity<0.001, P=0.013) and the dominant model (OR = 0.72, 95% CI = 0.55–0.94, Pheterogeneity<0.001, P=0.016) (Table 3). This evidence concerns the gene IL21 and rheumatoid arthritis.