A Methylenetetrahydrofolate Reductase Polymorphism and the Risk of Colorectal Cancer

摘要: We examined the relationship of a common polymorphism (667C→T) methylenetetrahydrofolate reductase (MTHFR) gene with risk colorectal cancer in case-control study conducted Health Professionals Follow-up Study. MTHFR genotypes were ascertained from blood samples among 144 men previously diagnosed and 627 controls. The adjusted odds ratio (OR) for variant homozygous ( val/val ) genotype was 0.57 [95% confidence interval (CI), 0.30–1.06]. High dietary intake methionine (OR, 0.27; 95% CI, 0.06–1.20) low consumption alcohol 0.11; 0.01–0.85) associated reduced incidence cancer. Alcohol stronger factor P , trend = 0.01), five or more alcoholic drinks per week abolished individuals interaction 0.02). inverse association slightly genotype. These data suggest that methyl supply is particularly critical individuals. When high, may be at probably because higher levels 5,10-methylenetetrahydrofolate prevent imbalances nucleotide pools during DNA synthesis. In contrast, when 5-methyltetrahydrofolate depleted by consumption, less able to compensate, leading potentially oncogenic alterations methylation.