Gene polymorphisms of an interleukin-23 receptor associated with susceptibility to rheumatoid arthritis in the Western Chinese Han population

Rheumatoid arthritis (RA) is a chronic inflammatory disease which is closely related to genetic background. Single-nucleotide polymorphisms (SNPs) have been found to play an important role in the development of RA. This study intends to investigate the links between gene polymorphisms in the interleukin-23 receptor (IL23R) and interleukin 17A (IL17A) and susceptibility to RA in the Western Chinese Han population. Four SNPs (rs6693831 T > C, rs1884444 G > T, and rs7517847 T > G in IL23R gene, and rs2275913 G > A in IL17A gene) were genotyped in 246 RA patients and 362 healthy controls by high resolution melting analysis. The comparative analyses among genotype distributions, clinical indicators, and IL-17A and IL-23R levels in RA patients were also performed. The study revealed that the SNP rs6693831 and rs1884444 of IL23R had a significant association with RA susceptibility. The frequencies of rs6693831 genotype CC and allele C were significantly higher in the RA group and associated with higher RA risk compared with genotype TT and allele T (OR = 7.797, 95% confidence interval [CI] = 4.072-14.932 and OR = 5.984, 95%CI = 3.190-11.224, respectively). The TT genotype of rs1884444 appeared to decrease the RA risk compared with the GG genotype (OR = .251, 95%CI = .118-.536). The genotype CC and allele C of rs6693831 and the genotype GG and allele G of rs1884444 may be risk factors for RA. IL23R gene polymorphisms may be involved in the risk of RA susceptibility in the Western Chinese Han population.