title: Association of homocysteine with type 2 diabetes: a meta-analysis implementing Mendelian randomization approach.
abstract: BACKGROUND
  We tested the hypothesis that elevated homocysteine (Hcy) level is causally associated with increased risk of type 2 diabetes mellitus (T2DM).
  
  
  RESULTS
  The meta-analysis and Mendelian randomization analysis were performed among 4011 cases and 4303 controls. The absolute pooled mean Hcy concentration in subjects with MTHFR 677TT was 5.55 μmol/L (95% CI, 1.33 to 9.77) greater than that in subjects with MTHFR 677CC in T2DM. Overall, the T allele of the MTHFR 677 C > T conferred a greater risk for T2DM [Random effect (RE) OR = 1.31(1.17-1.64), I² = 41.0%, p = 0.055]. The random effect (RE) pooled OR associated with T2DM for MTHFR 677TT relative to the 677CC was [RE OR = 1.38(1.18-1.62)]. The fixed-effect pooled OR of the association for the MTHFR 677 TT vs CT was 1.29 (95% CI, 1.09-1.51). MTHFR 677 TT showed a significantly higher risk for T2DM compared with MTHFR 677 CC + CT [Fixed effect (FE) OR = 1.32(1.14-1.54), I² = 0.0%, p = 0.686]. The absolute pooled mean Hcy concentration in individuals with T2DM was 0.94 μmol/L (95% CI, 0.40-1.48) greater than that in control subjects. The estimated causal OR associated with T2DM was 1.29 for 5 μmol/L increment in Hcy.
  
  
  CONCLUSIONS
  Our findings provided strong evidence on the causal association of Hcy level with the development of T2DM.
authors: Tao
authors: T
authors: Huang
authors: JingJing
authors: J
authors: Ren
authors: Jinyan
authors: J
authors: Huang
authors: Department of Food Science and Nutrition, Zhejiang University, 268 Kaixuan Road, Hangzhou 310029, China. duoli@zju.edu.cn.
authors: Duo
authors: D
authors: Li
mesh_terms: D000483:Alleles; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000235:genetics*; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006710:Homocysteine / Q000097:blood*; D006801:Humans; D057182:Mendelian Randomization Analysis; D042965:Methylenetetrahydrofolate Reductase (NADPH2) / Q000235:genetics*; D012307:Risk Factors
chemical_list: D006710:Homocysteine; C573423:MTHFR protein, human; D042965:Methylenetetrahydrofolate Reductase (NADPH2)