IL21R and rheumatoid arthritis: Concerning the IL-21R rs3093301, the genotype AA (p = 0.0122, OR = 1.965, 95% CI = 1.153–3.348) and allele A (p = 0.0418, OR = 1.289, 95% CI = 1.009–1.646) were higher in RA patients than in CSs, similar to the recessive genetic model of the A allele (p = 0.0077, OR = 0.512, 95% CI = 0.312–0.843).