title: A meta-analysis of the MTHFR C677T polymorphism and schizophrenia risk.
abstract: Epigenetic mechanisms such as methylation of DNA, could lead to abnormal neurodevelopment and may be important in the etiology of schizophrenia. Maternal dietary folate intake may play a role in determining methylation levels. The MTHFR gene C677T polymorphism influences folate metabolism and intracellular availability of folate metabolites for methylation. We carried out a meta-analysis of MTHFR C677T genotype and schizophrenia risk, and found that TT homozygotes had a significantly increased risk, OR 1.48 (1.18-1.86). This supports the hypothesis that folate status is a determinant of schizophrenia risk. Larger studies of this issue are required, together with studies of maternal genotype which could identify whether maternal folate status during pregnancy is important.
authors.affiliation: Department of Social Medicine, University of Bristol, Bristol, United Kingdom. s.j.lewis@bristol.ac.uk
authors.forename: Sarah J
authors.initials: SJ
authors.lastname: Lewis
authors.forename: Stanley
authors.initials: S
authors.lastname: Zammit
authors.forename: David
authors.initials: D
authors.lastname: Gunnell
authors.forename: George Davey
authors.initials: GD
authors.lastname: Smith
mesh_terms: D000483:Alleles; D005260:Female; D005787:Gene Frequency; D005838:Genotype; D006801:Humans; D008297:Male; D042965:Methylenetetrahydrofolate Reductase (NADPH2) / Q000235:genetics*; D011110:Polymorphism, Genetic; D012307:Risk Factors; D012559:Schizophrenia / Q000201:enzymology / Q000235:genetics*
chemical_list: D042965:Methylenetetrahydrofolate Reductase (NADPH2)