Zhao et al. conducted a meta-analysis of 31 case-control studies and found that ALDH2*2/*2 was associated with a reduced risk of esophageal cancer (OR = 0.69, 95% CI: 0.48–0.98) while ALDH2*1/*2 was associated with an increased esophageal cancer risk (OR = 2.34, 95% CI: 1.75–3.13) [31]. Here, ALDH2 is linked to esophageal cancer.