When we combined the ALDH2/ADH1B polymorphisms, those homozygous for the major allele for both rs671 and rs1229984 (GG and TT) presented increased risk of breast cancer in ever drinkers (OR = 1.76, 95% CI = 1.22–2.57, P-value 0.003) and those who consumed 12 g alcohol or more per day (OR = 3.37, 95% CI = 1.59–7.22, P-value = 0.002). This evidence concerns the gene ADH1B and breast cancer.