Association study between CYP17 gene polymorphism and endometriosis risk: a meta-analysis

The cytochrome P450 subfamily 17 (CYP17) gene T > C polymorphism is associated with endometriosis risk. However, studies on the association between the genotyping of MspA1 polymorphism in the 5'-untranslated region of the CYP17 gene and endometriosis risk have reported controversial results. The aim of the present study was to obtain a more precise estimate of the relationship of CYP17 gene polymorphism with endometriosis risk. Relevant articles published up to April 2014 were obtained from Pubmed, Embase, and Cochrane Central electronic databases. Case-control studies about the association between CYP17 gene polymorphisms and endometriosis were selected. Eligible data were extracted by two independent reviewers. The strength of the association between CYP17 and endometriosis was assessed by pooled odds ratios (OR) with 95% confidence intervals (CI). Eligible case-control studies involving 1000 cases and 1167 controls were analyzed from 280 studies. The pooled results showed no association between the CYP17 gene T > C polymorphism and endometriosis risk in the overall population (CC vs TT: OR = 0.92, 95% CI = 0.52-1.61, P = 0.762; TC vs TT: OR = 1.01, 95% CI = 0.72-1.42, P = 0.949; dominant model: OR = 0.94, 95% CI = 0.64-1.39, P = 0.763; recessive model: OR = 0.93, 95% CI = 0.64-1.35, P = 0.712). In the subgroup analysis based on ethnicity, no significant association was found in Asians, Caucasians and mixed population under a recessive model (Asians: OR = 0.76, 95% CI = 0.53-1.07, P = 0.118; Caucasians: OR = 2.47, 95% CI = 0.45-13.66, P = 0.300; mixed population: OR = 1.40, 95% CI = 0.65-3.02, P = 0.712). In conclusion, the meta-analysis suggested that the CYP17 gene polymorphism was not associated with endometriosis risk. Considering the limited sample size and ethnicity included in our meta-analysis, an updated meta-analysis needs to be conducted when larger and more well-designed studies are published.