Interaction between ADH1C Arg272Gln and alcohol intake in relation to breast cancer risk suggests that ethanol is the causal factor in alcohol related breast cancer

Alcohol is a risk factor for breast cancer. We wanted to determine if ADH polymorphisms which modify the rate of ethanol oxidation to acetaldehyde, were associated with breast cancer risk. We matched 809 postmenopausal breast cancer cases with 809 controls, nested within the prospective Diet, Cancer and Health study. variant allele carriers of ADH1C Arg272Gln, alcohol intake increased the risk of breast cancer with 14% (95% CI: 1.04–1.24) per 10 g alcohol/day, but not among homozygous wild type carriers (p for interaction = 0.06). Thus, slow oxidation of ethanol seemed to be associated with breast cancer risk.