IL17C and rheumatoid arthritis: In model with mutual adjustment for IL17A, IL17C, IL17D, IL17RA, IL17RC and IL17RD, the association between IL17RA and risk of RA was significant (nSNP = 52, OR = 1.049, 95% CI: 0.997–1.102, p.adj = 0.014, Table2).