descent but is essentially absent in people of European or African descent (Oota et al. 2004; Hurley et al. 2002). People carrying an ALDH2*2 allele show an alcohol flush reaction, even when they consume only relatively small amounts of alcohol (Peng et al. 2002). In these people, acetaldehyde levels in the blood increase from nearly undetectable levels to levels high enough to trigger the highly aversive reaction that includes severe flushing, nausea, and tachycardia, a reaction similar to that when disulfiram is present.
