Polymorphisms in the methylenetetrahydrofolate reductase (MTHFR) gene, intakes of folate and related B vitamins and colorectal cancer: a case-control study in a population with relatively low folate intake

Sharp, L., Little, J., Brockton, N., Cotton, S., Masson, L., Haites, N. and Cassidy, J. (2008) Polymorphisms in the methylenetetrahydrofolate reductase (MTHFR) gene, intakes of folate and related B vitamins and colorectal cancer: a case-control study in a population with relatively low folate intake. British Journal of Nutrition, 99(2), pp. 379-389. (doi: 10.1017/S0007114507801073)

Abstract

Folate is key in one-carbon metabolism, disruption of which can interfere with DNA synthesis, repair, and methylation. Efficient one-carbon metabolism requires other B vitamins and the optimal activity of enzymes including 5,10-methylenetetratiydrofolate reductase (MTHFR). We report a population-based case-control study of folate intake, related dietary factors and MTHFR polymorphisms (C677T, A1298C) and colorectal cancer in a Population with relatively high colorectal cancer incidence and relatively low folate intake. A total of 264 cases with histologically confirmed incident colorectal cancer and 408 controls participated. There was no clear trend in risk with reported intakes of total, or dietary, folate, riboflavin, vitamin 131, or vitamin 136, nor were there interactions between folate intake and the other B vitamins or alcohol. For C677T, risk decreased with increasing variant alleles (multivariate OR for CT v. CC = 0.77 (95% CI 0.52, 1-16); OR for TT 1). CC = 0.62 (95% CI 0.31, 1.24)), which, although not statistically significant, was consistent with previous studies. For A1298C, compared with AA subjects, CC Subjects had modest, non-significant, reduced risk (multivariate OR = 0.81 (95% CI 0.45, 1.49)). There were significant interactions between total folate and C677T (P=0.029) and A1298C (P=0.025), and total vitamin 136 and both polymorphisms (C677T, P=0.016; A1298C, P=0.033), although the patterns observed differed from previous studies. Seen against the setting of low folate intake, the results suggest that the role of folate metabolism in colorectal cancer aetiology may be more complex than previously thought. Investigation of particular folate vitamers (for example, tetrahydrofolate, 5,10-methylenetetrahydrofolate) may help clarify carcinogenesis pathways.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Cassidy, Professor James
• Authors: Sharp, L., Little, J., Brockton, N., Cotton, S., Masson, L., Haites, N., and Cassidy, J.
• College/School: College of Medical Veterinary and Life Sciences > School of Cancer Sciences
• Journal Name: British Journal of Nutrition
• Publisher: Cambridge University Press
• ISSN: 0007-1145
• Published Online: 06 December 2007