title: Genetic polymorphisms in folate metabolism and the risk of stomach cancer.
abstract: Folate deficiency has been implicated in the etiology of stomach cancer through abnormal DNA methylation and disrupted DNA synthesis and repair. Enzyme-coding genes involved in folate metabolism are often polymorphic. In a population-based study of 305 cases and 427 controls in Warsaw, Poland, we evaluated the risk of stomach cancer in relation to polymorphisms in folate-metabolizing genes, including MTHFR (Ex5+79C>T and Ex8-62A>C), MTR (Ex26-20A>G), and MTRR (Ex2-64A>G, Ex5+123C>T, Ex15+572C>T, Ex15-405A>T, Ex9-85C>T, Ex15-526G>A, and Ex14+14C>T). Polymorphisms in the MTHFR gene were not associated with stomach cancer risk. No notable effect was found for polymorphisms in MTR or MTRR either, although MTR Ex26-20 A>G and MTRR Ex5+123C>T polymorphisms were associated with a borderline increased risk of stomach cancer (MTR Ex26-20A>G, AG/GG versus AA: odds ratio, 1.35; 95% confidence interval, 0.96-1.90; MTRR Ex5+123C>T, CT/TT versus CC: odds ratio, 1.30; 95% confidence interval, 0.93-1.82). We did not find significant interactions between polymorphisms in MTHFR, MTR, and MTRR genes and dietary folate and alcohol consumption. Our study did not identify strong genetic determinants in the folate metabolism pathway for stomach cancer risk.
authors.affiliation: Division of Cancer Epidemiology and Genetics, Advanced Technology Center, National Cancer Institute, Gaithersburg, Maryland, USA. fz2004@columbia.edu
authors.forename: Fang Fang
authors.initials: FF
authors.lastname: Zhang
authors.forename: Mary Beth
authors.initials: MB
authors.lastname: Terry
authors.forename: Lifang
authors.initials: L
authors.lastname: Hou
authors.forename: Jinbo
authors.initials: J
authors.lastname: Chen
authors.forename: Jolanta
authors.initials: J
authors.lastname: Lissowska
authors.forename: Meredith
authors.initials: M
authors.lastname: Yeager
authors.forename: Witold
authors.initials: W
authors.lastname: Zatonski
authors.forename: Stephen
authors.initials: S
authors.lastname: Chanock
authors.forename: Alfredo
authors.initials: A
authors.lastname: Morabia
authors.forename: Wong-Ho
authors.initials: WH
authors.lastname: Chow
mesh_terms: D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D019175:DNA Methylation; D005260:Female; D005492:Folic Acid / Q000097:blood / Q000378:metabolism*; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006801:Humans; D008297:Male; D042965:Methylenetetrahydrofolate Reductase (NADPH2) / Q000235:genetics; D008875:Middle Aged; D016017:Odds Ratio; D011110:Polymorphism, Genetic; D012307:Risk Factors; D013274:Stomach Neoplasms / Q000097:blood / Q000378:metabolism*
chemical_list: D005492:Folic Acid; D042965:Methylenetetrahydrofolate Reductase (NADPH2)