title: A Meta-Analysis of Association between Methylenetetrahydrofolate Reductase Gene (MTHFR) 677C/T Polymorphism and Diabetic Retinopathy.
abstract: To shed light on the conflicting findings of the association between the methylenetetrahydrofolate reductase gene (MTHFR) 677C/T polymorphism and the risk of diabetic retinopathy (DR), a meta-analysis was conducted.
  
  
  
  A predefined search was performed on 1747 DR cases and 3146 controls from 18 published studies by searching electronic databases and reference lists of relevant articles. A random-effects or fixed-effects model was used to estimate the sizes of overall and stratification effects of the MTHFR 677C/T polymorphism on the risk of DR, as appropriate.
  
  
  
  Risks were evaluated by odds ratios (OR) with 95% confidence intervals (95% CI). We found a significant association between the MTHFR 677C/T polymorphism and the risk of DR for each genetic model (recessive model: OR = 1.67; 95% CI: 1.19-2.40 and dominant model: OR = 1.71; 95% CI: 1.28-2.28; respectively). In stratified analysis; we further found that the Asian group with both types of diabetes mellitus (DM) showed a significant association with genetic models (recessive model: OR = 2.16; 95% CI: 1.75-2.60 and dominant model: OR = 1.98; 95% CI: 1.42-2.76; respectively).
  
  
  
  Our study suggested that the MTHFR 677C/T polymorphism may contribute to DR development, especially in Asian populations. Prospective and additional genome-wide association studies (GWAS) are needed to clarify the real role of the MTHFR gene in determining susceptibility to DR.
authors: Department of Ophthalmology, Nanjing Medical University Affiliated Wuxi Second Hospital, 68 Zhongshan Road, Wuxi 214002, China. luoshasha403@163.com.
authors: Shasha
authors: S
authors: Luo
authors: Jiangsu Provincial Center for Disease Prevention and Control, 172 Jiangsu Road, Nanjing 210029, China. wangfuru1983@126.com.
authors: Furu
authors: F
authors: Wang
authors: Wuxi Center for Disease Control and Prevention, 499 Jincheng Road, Wuxi 214023, China. shichao.xo@163.com.
authors: Chao
authors: C
authors: Shi
authors: Department of Ophthalmology, Nanjing Medical University Affiliated Wuxi Second Hospital, 68 Zhongshan Road, Wuxi 214002, China. zhifengwu2013@126.com.
authors: Zhifeng
authors: Z
authors: Wu
mesh_terms: D044466:Asian People / Q000235:genetics; D003930:Diabetic Retinopathy / Q000235:genetics*; D020022:Genetic Predisposition to Disease; D006801:Humans; D042965:Methylenetetrahydrofolate Reductase (NADPH2) / Q000235:genetics*; D016017:Odds Ratio; D020641:Polymorphism, Single Nucleotide
chemical_list: D042965:Methylenetetrahydrofolate Reductase (NADPH2)
keywords: DM type; MTHFR 677C/T; diabetic retinopathy; ethnicity; polymorphism