MTHFR 677C>T Polymorphism Increases the Male Infertility Risk: A Meta-Analysis Involving 26 Studies

作者：Mancheng Gong, Wenjing Dong, Tingyu He, Zhirong Shi, Guiying Huang, Rui Ren, Si-Chong Huang, Shaopeng Qiu, Runqiang Yuan · 发表于：PLoS ONE · 年份：2015 · DOI：10.1371/journal.pone.0121147 · 被引用次数：61 · 研究领域：Folate and B Vitamins Research、Sperm and Testicular Function、Ovarian function and disorders

BACKGROUND AND OBJECTIVES: Methylenetetrahydrofolate reductase (MTHFR) polymorphism may be a risk factor for male infertility. However, the epidemiologic studies showed inconsistent results regarding MTHFR polymorphism and the risk of male infertility. Therefore, we performed a meta-analysis of published case-control studies to re-examine the controversy. METHODS: Electronic searches of PubMed, EMBASE, Google Scholar and China National Knowledge Infrastructure (CNKI) were conducted to select eligible literatures for this meta-analysis (updated to June 19, 2014). According to our inclusion criteria and the Newcastle-Ottawa Scale (NOS), only high quality studies that observed the association between MTHFR polymorphism and male infertility risk were included. Crude odds ratio (OR) with 95% confidence interval (CI) was used to assess the strength of association between the MTHFR polymorphism and male infertility risk. RESULTS: Twenty-six studies involving 5,575 cases and 5,447 controls were recruited. Overall, MTHFR 677C>T polymorphism showed significant associations with male infertility risk in both fixed effects (CT+TT vs. CC: OR = 1.34, 95% CI: 1.23-1.46) and random effects models (CT+TT vs. CC: OR = 1.39, 95% CI: 1.19-1.62). Further, when stratified by ethnicity, sperm concentration and control sources, the similar results were observed in Asians, Caucasians, Azoo or OAT subgroup and both in population-based and hospital-based controls. Nevertheless, no significant associati...