Authors of a study published in the journal ‘The Breast’ state that alcohol’s effect on women who carry a BRCA gene mutation is unclear.
The researchers conducted a case-control study of 1925 matched pairs of predominantly premenopausal women who carry a BRCA1 or a BRCA2 mutation. Information on current alcohol consumption was obtained from a questionnaire administered during the course of genetic counselling or at the time of enrolment.
A modest inverse association between breast cancer and reported current alcohol consumption was observed among women with a BRCA1 mutation (OR = 0.82, 95% CI 0.70–0.96), but not among women with a BRCA2 mutation (OR = 1.00; 95% CI 0.71–1.41).
The study concluded that compared to non-drinkers, exclusive consumption of wine was associated with a significant reduction in the risk of breast cancer among BRCA1 carriers (p-trend = 0.01).
Alcohol consumption does not appear to increase breast cancer risk in women carrying a BRCA gene mutation.

Source: Alcohol consumption and the risk of breast cancer among BRCA1 and BRCA2 mutation carriers The Breast, In Press, Corrected Proof, Available online 12 June 2010.