Association of IL-17A (rs2275913) G/A and IL-21 (rs4833837) C/T Gene Polymorphisms in Iraqi patients with Rheumatoid Arthritis

cytokines, such as interleukin (17A )and interleukin (21), genetic variation, and environmental variables induce it. The purpose of this study is to examine IL-17A (rs2275913) G/A and IL-21 (rs4833837) C/T gene polymorphism association in Iraqi patients with rheumatoid arthritis. The current study includes 120 subjects classified into two main groups: 60 RA patients and 60 healthy controls. Tetra ARMS-PCR and Allele-specific PCR were used for the detection of IL-17A and IL-21 gene polymorphisms respectively. Genotype and allele frequency results of IL17 rs2275913 G/A and IL-21 rs4833837 C/T gene polymorphisms were analyzed under codominant, dominant, recessive, and additive models. IL17A (rs2275913) G/A under codominant pattern with heterozygous genotype (G/A) and dominant pattern, those of the GA+AA genotypes significantly higher in RA patients with respect to those of the control group (OR:3.3, CI 95%: ( 1.11 to 9.96), P< 0.03) and (OR: 3.35, CI 95%: ( 1.12 to 9.99), P< 0.03) respectively. In addition, this genetic polymorphism doesn’t appear significant variation in other inheritance models. The allele (A) frequency was observed to be higher in RA patients (49%) opposite the allele (G) frequency observed to be higher in control (59%) without significant variation between them, On the other hand, IL-21 rs4833837 C/T genotyping and allele frequencies results revealed no significant variation between the rheumatoid arthritis patients in comparison with the control groups.