ALDH2 and cancer: In the present study, heavy drinkers with ALDH2*2/2*2, ALDH2*1/2*2, and ALDH2*1/2*1 genotypes comprised 3.9%, 25.5%, and 14.7% of the cancer group, and 2.5%, 20.0%, and 0.8% of the control group, respectively.