ALDH2*2 and peer drinking in East Asian college students

ABSTRACT

Background: The ALDH2*2 allele (A-allele) at rs671 is more commonly carried by Asians and is associated with alcohol-related flushing, a strong adverse reaction to alcohol that is protective against drinking. Social factors, such as having friends who binge drink, also contribute to drinking in Asian youth. Objectives: This study examined the interplay between ALDH2*2, peer drinking, and alcohol consumption in college students. We hypothesized that the relationship between ALDH2*2 and standard grams of ethanol per month would vary based on the level of peer drinking. Methods: Subjects (N = 318, 63.25% female) were East Asian college students in the United States who reported drinking alcohol. Data were from the freshman year of a university survey that included a saliva DNA sample. ALDH2*2 status was coded ALDH2*2(+) (A/G and A/A genotypes) and ALDH2*2(−) (G/G genotype). Peer drinking was students’ perception of how many of their friends “got drunk”. Results: Main effects of ALDH2*2(−) and having more friends who got drunk were associated with greater alcohol consumption. The ALDH2*2 × peer drunkenness interaction showed a stronger positive association with alcohol consumption for ALDH2*2(−) versus ALDH2*2(+) at increasing levels of peer drunkenness. Follow-up comparisons within each peer drunkenness level identified significantly higher alcohol consumption for ALDH2*2(−) compared to ALDH2*2(+) at the all friends got drunk level.

Conclusion: There was evidence of a stronger effect for ALDH2*2(−) compared to ALDH2*2(+) with greater alcohol use when students were more exposed to peer drinking. Findings contribute to a growing literature on the interrelationships between genetic influences and more permissive environments for alcohol consumption.

KEYWORDS:

• ALDH2*2
• alcohol consumption
• college students
• peer drinking
• gene-environment effects
• genotype

Acknowledgments

We would like to thank the VCU students for making this study a success, as well as the many VCU faculty, students, and staff who contributed to the design and implementation of the project. We are grateful to Clare Tiarsmith for her work in preparing this manuscript for publication.

Declaration of interest

The authors report no relevant financial conflicts.

Funding

This work is, in part, supported by K01AA021145 from the National Institute on Alcohol Abuse and Alcoholism. Spit for Science: The VCU Student Survey has been supported by Virginia Commonwealth University, P20AA107828, R37AA011408, K02AA018755, and P50AA022537 from the National Institute on Alcohol Abuse and Alcoholism, and UL1RR031990 from the National Center for Research Resources and National Institutes of Health Roadmap for Medical Research.

Additional information

Funding

This work is, in part, supported by K01AA021145 from the National Institute on Alcohol Abuse and Alcoholism. Spit for Science: The VCU Student Survey has been supported by Virginia Commonwealth University, P20AA107828, R37AA011408, K02AA018755, and P50AA022537 from the National Institute on Alcohol Abuse and Alcoholism, and UL1RR031990 from the National Center for Research Resources and National Institutes of Health Roadmap for Medical Research.