Self-reported alcohol-associated symptoms and drinking behavior in three ALDH2 genotypes among Japanese university...

Alcohol abuse is one of the most serious health problems among young adults. Nearly half of the Japanese population is sensitive to alcohol due to a genetic polymorphism in low K(m) aldehyde dehydrogenase (ALDH2). In the present study, we investigated the effects of the ALDH2 genotype on both self-reported alcohol-associated symptoms and alcohol drinking behavior among Japanese university students.

The study subjects were 423 (389 males and 34 females) university students in a medical university. The subjects completed a questionnaire regarding self-reported alcohol-associated symptoms and alcohol drinking behavior. The ALDH2 genotype was determined through digestion of polymerase chain reaction (PCR) products by a restriction enzyme Ksp632I. The frequency of alcohol-associated symptoms generally increased in the order ALDH2*1/*1, ALDH2*1/*2, ALDH2*2/*2 among males. The frequency of those who drink > or = 5 days/week was less than 10% in all genotype groups. However, the frequency of those who drink 1-4 days/week was significantly higher in ALDH2*1/*1 than that in ALDH2*1/*2 and in ALDH2*2/*2. A similar tendency also was observed in females. Mean amounts of alcohol consumption per occasion in the three ALDH2 genotypes stratified by drinking frequency generally increased significantly in the order ALDH2*2/*2, ALDH2*1/*2, ALDH2*1/*1 in both sexes. The proportion of binge drinkers defined by those who drink ethanol of > or = 75 ml per occasion on average also increased in the order ALDH2*2/*2 (0.0%), ALDH2*1/*2 (9.8%), ALDH2*1/*1 (22.1%) among male drinkers (> or = 1 day/month).

We for the first time demonstrated clear associations between the ALDH2 genotype, self-reported alcohol-associated symptoms, and alcohol drinking behavior among Japanese university students.