In addition, the association between ALDH2*1/*2 and esophageal cancer became stronger with higher level of alcohol consumption (never drinker: OR = 1.21, 95% CI: 0.95–1.73; light drinker: OR = 3.79, 95% CI: 3.04–4.72; heavy drinker: OR = 6.50, 95% CI: 5.34–7.92) [31]. This evidence concerns the gene ALDH2 and esophageal cancer.