POLYMORPHISM IN ALDH2-GENOTYPE IN JAPANESE MEN AND THE ALCOHOL-BLOOD PRESSURE RELATIONSHIP

Aldehyde dehydrogenase with a low Michaelis constant (K-m), ALDH2, is a major enzyme involved in the conversion of acetaldehyde, a toxic met abolite of ethanol, into acetic acid in the liver. Inherited deficienc y of ALDH2 activity is found in half of Japanese, and is characterized by ''Oriental flushing'' after alcohol consumption. The aim of the pr esent study is to evaluate the influence of the genetic polymorphism i n alcohol metabolism on the sensitivity to the presser effect of alcoh ol. Genotypes of ALDH2 were determined in 403 middle-aged Japanese men using genomic DNA extracted from white blood cells. Two hundred and f orty-three (60%) of the subjects were shown to be homozygotes for the normal ALDH2 gene, 25 (6%) of the subjects were homozygotes for the mu tant ALDH2 gene, and the remaining 135 (33%) were heterozygotes. None of the homozygotes for the mutant gene drank enough to show the presse r effect of alcohol. Elevations of blood pressure associated with incr easing alcohol consumption or with elevations of serum gamma-glutamyl transpeptide (GTP) level were not different between the other two ALDH 2-genotypes. It can be concluded that polymorphism in the ALDH2-genoty pe found in Japanese men does not affect the individual sensitivity to the presser effect of alcohol.