Deleterious pleiotropic effects of the atypical aldehyde dehydrogenase 2 (ALDH2) allele: comment on Luo et al., 2005

Luo Biochem. Genet. 43:223-227] concluded, "The mutation ALDH2(() 487Lys allele is not deleterious but is of great benefit to human health." This statement is easily subject to misinterpretation and needs to be clarified. Their results actually show there is a pleiotropic effect associated with the mutation ALDH2(() 487Lys allele that is as deleterious as the risk of alcoholism for which it offers protection, and thus there is no net benefit from having the mutation. A clarification is needed because this statement and others in the paper might be used inappropriately as an endorsement of practices that are in fact worthless, because it masks the need to find what the pleiotropic effect is, and because it seems to contradict what otherwise seems to be a general rule of evolution.