title: Are MTHFR C677T and MTRR A66G Polymorphisms Associated with Overweight/Obesity Risk? From a Case-Control to a Meta-Analysis of 30,327 Subjects.
abstract: Several studies have examined the associations of methylenetetrahydrofolate reductase (MTHFR) C677T and methionine synthase reductase (MTRR) A66G polymorphisms with being overweight/obesity. However, the results are still controversial. We therefore conducted a case-control study (517 cases and 741 controls) in a Chinese Han population and then performed a meta-analysis by combining previous studies (5431 cases and 24,896 controls). In our case-control study, the MTHFR C677T polymorphism was not significantly associated with being overweight/obesity when examining homozygous codominant, heterozygous codominant, dominant, recessive and allelic genetic models. The following meta-analysis confirmed our case-control results. Heterogeneity was minimal in the overall analysis, and sensitivity analyses and publication bias tests indicated that the meta-analytic results were reliable. Similarly, both the case-control study and meta-analysis found no significant association between the MTRR A66G polymorphism and being overweight/obesity. However, sensitivity analyses showed that the associations between the MTRR A66G polymorphism and being overweight/obesity became significant in the dominant, heterozygous codominant and allelic models after excluding our case-control study. The results from our case-control study and meta-analysis suggest that both of the two polymorphisms are not associated with being overweight/obesity. Further large-scale population-based studies, especially for the MTRR A66G polymorphism, are still needed to confirm or refute our findings.
authors.affiliation: Research Center of Environment and Non-Communicable Disease, School of Public Health, China Medical University, Shenyang 110013, China. fanfan0721ykl@163.com.
authors.forename: Shu-Jun
authors.initials: SJ
authors.lastname: Fan
authors.affiliation: Research Center of Environment and Non-Communicable Disease, School of Public Health, China Medical University, Shenyang 110013, China. boyiyangcmu@163.com.
authors.forename: Bo-Yi
authors.initials: BY
authors.lastname: Yang
authors.affiliation: Research Center of Environment and Non-Communicable Disease, School of Public Health, China Medical University, Shenyang 110013, China. zhixy90smile@126.com.
authors.forename: Xue-Yuan
authors.initials: XY
authors.lastname: Zhi
authors.affiliation: Research Center of Environment and Non-Communicable Disease, School of Public Health, China Medical University, Shenyang 110013, China. hemiao.cmu@gmail.com.
authors.forename: Miao
authors.initials: M
authors.lastname: He
authors.affiliation: Research Center of Environment and Non-Communicable Disease, School of Public Health, China Medical University, Shenyang 110013, China. 472594283@163.com.
authors.forename: Da
authors.initials: D
authors.lastname: Wang
authors.affiliation: Division of Molecular Preventive Medicine, Shanghai Institute of Targeted Therapy and Molecular Medicine, Shanghai 200433, China. wangyanxun@genechina.com.
authors.forename: Yan-Xun
authors.initials: YX
authors.lastname: Wang
authors.affiliation: Division of Molecular Preventive Medicine, Shanghai Institute of Targeted Therapy and Molecular Medicine, Shanghai 200433, China. wangyanxun@genechina.com.
authors.forename: Yi-Nuo
authors.initials: YN
authors.lastname: Wang
authors.affiliation: Brain Disease Center, Tianjin Dagang Oil Field General Hospital, Tianjin 300280, China. weijiantianjin@163.com.
authors.forename: Jian
authors.initials: J
authors.lastname: Wei
authors.affiliation: Research Center of Environment and Non-Communicable Disease, School of Public Health, China Medical University, Shenyang 110013, China. qmzheng@mail.cmu.edu.cn.
authors.forename: Quan-Mei
authors.initials: QM
authors.lastname: Zheng
authors.affiliation: Research Center of Environment and Non-Communicable Disease, School of Public Health, China Medical University, Shenyang 110013, China. sungf@mail.cmu.edu.cn.
authors.forename: Gui-Fan
authors.initials: GF
authors.lastname: Sun
mesh_terms: D000328:Adult; D044466:Asian People / Q000235:genetics*; D016022:Case-Control Studies; D002681:China; D005260:Female; D005287:Ferredoxin-NADP Reductase / Q000235:genetics*; D056726:Genetic Association Studies; D020022:Genetic Predisposition to Disease; D006801:Humans; D008297:Male; D042965:Methylenetetrahydrofolate Reductase (NADPH2) / Q000235:genetics*; D008875:Middle Aged; D009765:Obesity / Q000235:genetics*; D050177:Overweight / Q000235:genetics*; D020641:Polymorphism, Single Nucleotide
chemical_list: C111241:methionine synthase reductase; D005287:Ferredoxin-NADP Reductase; C573423:MTHFR protein, human; D042965:Methylenetetrahydrofolate Reductase (NADPH2)
keywords: MTHFR; MTRR; obesity; overweight; polymorphism