Associations between ERAP1 polymorphisms and susceptibility to ankylosing spondylitis: a meta-analysis

The aim of this study was to determine whether 11 polymorphisms of endoplasmic reticulum aminopeptidase 1 (ERAP1) confer susceptibility to ankylosing spondylitis (AS). The authors conducted meta-analyses on associations between ERAP1 polymorphisms and AS susceptibility by using fixed and random effects models. A total of 19 articles were included in this meta-analysis, which comprised a total of 19,902 AS patients and 39,750 controls. The meta-analysis revealed a significant association between AS and the minor alleles of the rs30187 polymorphism in all study subjects (OR = 1.255, 95 % CI = 1.147–1.373, P = 8.0 × 10⁻⁸). Stratification by ethnicity led to the identification of a significant association between this polymorphism and AS in European patients (OR = 1.283, 95 % CI = 1.237–1.331, P < 1.0 × 10⁻⁹). Meta-analyses of the results for the rs27044, rs10050860, rs2287987, rs17482078, and rs26653 polymorphisms showed the same pattern that was found for rs30187. Interestingly, the rs27037 polymorphism was significantly associated with AS susceptibility in both European and Asian patients. Meta-analysis showed a significant association between AS and the minor alleles of the rs27980 and rs27582 polymorphisms in the East Asian patients (OR = 0.904, 95 % CI = 0.818–0.999, P = 0.047; OR = 0.871, 95 % CI = 0.772–0.982, P = 0.024, respectively) (Table 2). However, these polymorphisms have not been studied in Europeans. This meta-analysis shows that the ERAP1 polymorphisms are associated with the development of AS in Europeans and East Asians.