RTKN2 and rheumatoid arthritis: However, after reviewing the location of the reported RA-associated variants, we found that very few variants are located in the exome area, including CTLA4 (rs231775), FCGR2A (rs1801274), IL6R (rs2228145), OLIG3 (rs2230926), PTPN22 (rs2476601), RTKN2 (rs3125734), SH2B3 (rs3184504), TNFAIP3 (rs223092) and TYK2 (rs34536443).