[Note: See also the explanatory NIH news release on this study, "Essential nutrient found in eggs reduces risk of breast cancer by 24%: Most women consume too little."]
Choline is an essential nutrient required for methyl group metabolism, but its role in carcinogenesis and tumor progression is not well understood. By utilizing a population-based study of 1,508 cases and 1,556 controls, we investigated the associations of dietary intake of choline and two related micronutrients, methionine and betaine, and risk of breast cancer.
The highest quintile of choline consumption was associated with a lower risk of breast cancer [odds ratio (OR): 0.76; 95% confidence interval (CI): 0.58-1.00] compared with the lowest quintile.
Two putatively functional single nucleotide polymorphisms of choline-metabolizing genes, PEMT -774G>C (rs12325817) and CHDH +432G>T (rs12676), were also found be related to breast cancer risk.
Compared with the PEMT GG genotype, the variant CC genotype was associated with an increased risk of breast cancer (OR: 1.30; 95% CI: 1.01-1.67).
The CHDH minor T allele was also associated with an increased risk (OR: 1.19; 95% CI: 1.00-1.41) compared with the major G allele. The BHMT rs3733890 polymorphism was also examined but was found not to be associated with breast cancer risk.
We observed a significant interaction between dietary betaine intake and the PEMT rs7926 polymorphism (Pinteraction=0.04).
Our findings suggest that choline metabolism may play an important role in breast cancer etiology.
Source: The FASEB Journal, June 1 2008; 22(6) [Epub ahead of print] PMID: 18230680 Xu X, Gammon MD, Zeisel SH, Lee YL, Wetmur JG, Teitelbaum SL, Bradshaw PT, Neugut AI, Santella RM, Chen J. Departments of Community and Preventive Medicine, Microbiology, Genetics and Genomic Sciences, Pediatrics, and Oncological Science, Mount Sinai School of Medicine, New York; Departments of Epidemiology and Nutrition, University of North Carolina, Chapel Hill, North Carolina; Departments of Epidemiology, Medicine, and Environmental Health Sciences, Columbia University, New York, USA.