In Europeans, in whom the ALDH2 mutant allele at residue 487 is almost absent, a large multicentre study [27] has shown a significantly increased risk of cancer of the upper aerodigestive tract in individuals who were heterozygous or homozygous for any ALDH2 variants at residues +84, +348, and -241 and who drank moderately or heavily; a significant interaction was noted between alcohol consumption and ALDH2 +348 and -241 polymorphisms [27]. This evidence concerns the gene ALDH2 and cancer.