TNF-α-857 and-1031 polymorphisms predict good therapeutic response to TNF-α blockers in Chinese Han patients with ankylosing spondylitis

Aim: To evaluate whether polymorphisms at -857, -1031, -308 and -238 positions of the TNF-alpha gene influence response to TNF-alpha-blocker therapy in Chinese Han patients with ankylosing spondylitis. Patients & methods: A total of 106 patients with ankylosing spondylitis were recruited and genotyped for -857, -1031, -308 and -238 TNF-alpha gene polymorphisms. In total, 32 received infliximab and 74 received a recombinant human TNF-alpha receptor II-IgG Fc fusion protein (rhTNFR-Fc). At the end of 12 weeks, patients were assessed using the Assessment of SpondyloArthritis International Society (ASAS) 20, 40, 50 and 70 criteria. Results: Polymorphisms at -308 and -238 did not affect therapeutic response. The -857 C/C genotype (p = 0.0021) responded better to therapy. The -1031 T/T genotype (p = 0.0004) showed better outcome. Conclusion: In Chinese Han ankylosing spondylitis patients, polymorphisms at the -308 and -238 positions of the TNF-alpha gene are unable to predict TNF-alpha-blocker response; however, -857 C/C and -1031 T/T genotypes have the ability to predict good response.