ALDH2 and hyperinsulinemic hypoglycemia, familial, 4: Furthermore, Japanese alcoholics deficient in the ability to detoxify ACH (ALDH2 deficiency) combined with enhanced ability to produce ACH from ethanol (highly active alcohol dehydrogenase [ADH] enzyme) show markedly enhanced DNA damage characterized by elevated levels of N2-ethylidene-dG adducts in blood DNA [18].