Previous studies implicated that IL17/IL23 pathway and TH17 cells play an important role in autoimmune inflammation. Genome wide association studies have identified multiple single nucleotide polymorphisms (SNPs) in the IL23R and IL17 genes region associated with rheumatoid arthritis (RA).
In this study, we investigated the association of IL23R, IL17A and IL17F genes SNPs with RA susceptibility in the Algerian population. 343 patients with RA and 323 healthy subjects were genotyped for IL23R (rs11209026, rs1343151, rs10489629), IL17F (rs763780, rs2397084) and IL17A (rs2275913) variants by TaqMan technology.
There was no evidence of a genetic association between IL23R, IL17F and IL17A SNPs and RA susceptibility in our population. However, IL23R rs1343151 variant enhanced the development of RF IgM and IgG positive (+) RA as compared with RF IgM and IgG negative (-) RA (OR 2.29, p = 0.004 and OR 0.64, p = 0.014 respectively). Also, IL23R rs10489629 was associated with all RF isotypes positive disease (IgM+: OR 2.16, p = 0,006; IgG+: OR 0.64, p = 0,004 and IgA+: OR 1.54, p = 0,013). A moderate association of IL17A rs2275913 with RF IgA- RA subgroup was shown (OR 1.95, p = 0,039). Moreover, our data showed a correlation between IL23R and IL17F variants and the parameters of disease activity such as HAQ score and disease duration.
The current study emphasizes the lack of association of IL23R and IL17 polymorphisms with RA susceptibility in the Algerian population. However, the data showed the relationship between IL23R and IL17A polymorphisms and the production of the different RF isotypes in RA patients.