BRCA1 and breast cancer: The authors, in a case-control study conducted on 1097 BRCA1 and 2 mutated women vs healthy women, found no significant association between the 2 groups considered (mutated vs healthy women) whether they were smokers or ex smokers or the age at which smoking began within 5 years of menarche (OR = 1.03;95% CI = 0.90 to 1.33) or before the first pregnancy concluding that smoking could not be a breast cancer risk in carriers of BRCA mutations.