ALDH2 and esophageal squamous cell carcinoma: Numerous studies targeting certain genes have reported an association of genetic polymorphisms, including CYP1A1, CYP2E1, and MTHFR, with ESCC risk in the Chinese population.52 In particular, the ADH1*47 Arg, ALDH2*2, and MTHFR 677 TT genotypes appear to act synergistically with alcohol consumption.53–55