Alcohol metabolism in Asian-American men with genetic polymorphisms of aldehyde dehydrogenase

Ann Intern Med. 1997 Sep 1;127(5):376-9. doi: 10.7326/0003-4819-127-5-199709010-00007.


Background: About half of certain Asians have a deficiency of the low-Km aldehyde dehydrogenase (ALDH2) isoenzyme. This deficiency results from inheritance of a mutant ALDH2*2 allele.

Objective: To determine whether Asian Americans with ALDH2*2 alleles differ from Asian Americans without this mutation in terms of blood levels of alcohol and acetaldehyde after ingestion of a moderate amount of alcohol.

Design: Double-blind, crossover study.

Setting: Private research institute.

Participants: 35 healthy Asian-American men. Three men who became ill after alcohol ingestion and one who had outlying data were excluded.

Intervention: Alcoholic beverage, containing 0.56 g of alcohol per kg of body weight, or placebo beverage, containing 3 mL of alcohol, given orally on separate occasions.

Measurements: Blood levels of alcohol and acetaldehyde measured before and several times after ingestion of the alcoholic or placebo beverage.

Results: Participants with ALDH2*2 alleles had significantly higher blood acetaldehyde levels after ingesting alcoholic and placebo beverages than did participants with ALDH2*1 alleles, despite similar blood alcohol concentrations.

Conclusions: Blood acetaldehyde levels rather than blood alcohol concentration may mediate enhanced alcohol sensitivity among Asians with ALDH2*2 alleles.

Publication types

  • Clinical Trial
  • Controlled Clinical Trial
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Acetaldehyde / blood*
  • Adult
  • Aldehyde Dehydrogenase / genetics*
  • Alleles
  • Asian Americans / genetics*
  • Cross-Over Studies
  • Double-Blind Method
  • Ethanol / blood*
  • Humans
  • Male
  • Polymorphism, Genetic*


  • Ethanol
  • Aldehyde Dehydrogenase
  • Acetaldehyde