Association Between Protein Tyrosine Phosphatase Non-Receptor Type 22 (PTPN22) Polymorphisms and Risk of Ankylosing Spondylitis: A Meta-analysis

BACKGROUND Ankylosing spondylitis (AS) is a chronic autoimmune disease that involves the imbalance of peripheral tolerance possibly caused by the negative signal of activated T cells. The polymorphisms in the human protein tyrosine phosphatase non-receptor type 22 (PTPN22) gene have been pointed out to be related to the pathogenesis of AS, but conclusions over this issue remain contradictory. We attempted to give a more precise conclusion about the effects of PTPN22 polymorphisms on AS risk by means of a meta-analysis. MATERIAL AND METHODS PubMed, Embase, Wanfang, and Chinese National Knowledge Infrastructure (CNKI) were searched for relevant studies published in the English or Chinese language. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated with a fixed- or random-effects model to evaluate the correlation between PTPN22 rs2488457, rs1217414, and rs2476601 polymorphisms and AS susceptibility. Sensitivity analysis was also carried out to detect the stability of the results. RESULTS The present meta-analysis showed a positive correlation of both PTPN22 rs2488457 and rs1217414 polymorphisms with AS risk under CC vs. GG, CC + GC vs. GG, CC vs. GC + GG, allele C vs. allele G (OR=1.39, 95% CI=1.04-1.85, P=0.646; OR=1.29, 95% CI=1.03-1.62, P=0.426; OR=1.26, 95% CI=1.02-1.56, P=0.971; OR=1.20, 95% CI=1.05-1.38, P=0.571), and TT vs. CC and TT vs. CT + CC models (OR=3.83, 95% CI=1.11-13.24, P=0.196; OR=3.83, 95% CI=1.09-13.42, P=0.244), respectively. CONCLUSIONS PTPN22 rs2488457 and rs1217414 polymorphisms may be risk factors for AS occurrence.