Interleukin -21 gene RS 2221903 polymorphisms in rheumatoid arthritis patients

Background: Rheusmatoid arthritis (RA) is a chronic systemic disease characterized by articular involvement and extra-articular manifestation. A cytokine with immunomodulatory properties, interleukin-21 (IL-21) influences both the innate and acquired immunity. The aim of this work was to detect IL-21 polymorphism (rs2221903) in cases with RA and determine its role in the pathogenesis and activity of the disease.Methods: This research was carried out on 60 cases with RA, cases were divided into three groups Group I: RA cases with an active form, group II: RA cases in inactive form, group III: apparently healthy individual who will be selected with matched age and sex.Results: There was statistically significant relationship between activity of RA and genotypes (P=0.04), three groups in the genotype distribution (p=0.016), reference (C) and variant allele (T) distribution (p=0.003) between the three groups and in genotype distribution between RA cases and control (P=0.003), this meaning that IL-21 is susceptibility locus for RA.Conclusions: Results indicate that IL-21(rs2221903) has a role in the pathogenesis and activity of RA. It is also susceptibility locus for RA.