title: Breast cancer risk in relation to alcohol consumption and BRCA gene mutations--a case-only study of gene-environment interaction.
abstract: The variable penetrance of the BRCA1 and BRCA2 genes suggests that other genetic or environmental factors may interact with these mutations to modify breast cancer risk. The objective of this study was to measure departures from multiplicative effects of alcohol consumption and BRCA gene mutations. A cohort of French-Canadian breast cancer patients was tested for BRCA gene mutations and completed a food frequency questionnaire. The case-only odds ratio (COR) was calculated. A total of 857 women, including 10 BRCA1 and 33 BRCA2 mutation carriers, participated in the study. No significant interaction between alcohol consumption and BRCA1 mutations was detected, although the interaction with wine consumption suggested a sub-multiplicative effect (COR = 0.38, 95% CI: 0.08-1.81). Consumption of alcohol other than wine interacted significantly with BRCA2 mutations (COR = 2.15, 95% CI: 1.03-4.49). Consumption of wine may protect against BRCA1-associated tumors, while women with BRCA2 mutations may be at greater risk of alcohol-induced breast cancer.
authors.affiliation: Department of Epidemiology and Community Medicine, University of Ottawa, Ottawa, Canada.
authors.forename: Jessica
authors.initials: J
authors.lastname: Dennis
authors.forename: Daniel
authors.initials: D
authors.lastname: Krewski
authors.forename: Frédérique-Sophie
authors.initials: FS
authors.lastname: Côté
authors.forename: Eve
authors.initials: E
authors.lastname: Fafard
authors.forename: Julian
authors.initials: J
authors.lastname: Little
authors.forename: Parviz
authors.initials: P
authors.lastname: Ghadirian
mesh_terms: D000328:Adult; D000428:Alcohol Drinking / Q000009:adverse effects*; D001943:Breast Neoplasms / Q000453:epidemiology* / Q000235:genetics; D002285:Carcinoma, Intraductal, Noninfiltrating / Q000453:epidemiology* / Q000235:genetics; D005260:Female; D059647:Gene-Environment Interaction; D019398:Genes, BRCA1; D024522:Genes, BRCA2; D006579:Heterozygote; D006801:Humans; D008875:Middle Aged; D009154:Mutation; D016017:Odds Ratio; D011110:Polymorphism, Genetic; D012307:Risk Factors; D014920:Wine