Association between oestrogen receptor alpha (ESR1) gene polymorphisms and endometriosis: a meta-analysis of 24 case-control studies

The PvuII (C > T), XbaI (A > G) and (TA)n polymorphisms of ESR1 gene are potentially associated with susceptibility to endometriosis. A meta-analysis was conducted to evaluate comprehensively the associations between endometriosis and ESR1 polymorphisms. Twenty-four studies, including 2740 cases and 3208 controls, were retrieved through searches of PubMed, EMBASE, Web of Science, CBM and CNKI. Meta-analyses showed that PvuII was associated with endometriosis only for stage I-III, only under a recessive model (OR = 1.53, 95% CI 1.05 to 2.21; P = 0.025). The short allele and TA13 of (TA)n were associated with a higher risk of endometriosis (ORS = 1.71, 95% CI 1.01 to 2.81, P = 0.046; ORTA13 = 1.45, 95% CI 1.06 to 1.97, PTA13 = 0.019); TA20 repeats was associated with a lower risk (OR = 0.36, 95% CI 0.16 to 0.80; P = 0.012). No statistically significant association was found in the XbaI polymorphism. This meta-analysis indicated that the PvuII and XbaI polymorphisms were not associated with the risk of endometriosis, whereas stage classification of endometriosis was likely to influence the association of PvuII polymorphism. The (TA)n polymorphisms might play roles in the susceptibility to, or protection against, the pathogenesis of endometriosis.