ALDH2 and early-onset autosomal dominant Alzheimer disease: ALDH2 is considered one of the most important enzymes for ethanol metabolism in vivo, and an inactivating mutation in ALDH2, the common East Asian ALDH2*2 (the rs671 E504K missense variant), is associated with a wide range of health complications, such as osteoporosis, cancer (about 20% increased cancer risk in inactive, ALDH2*2, homozygous individuals) and Alzheimer’s disease [8–10].