Among individuals with the ALDH2*2 allele, cancer risk demonstrates a clear dose-response relationship with alcohol consumption, with relative risks reported to be up to four times the relative risk, compared to non-carriers.<h4>Objectives</h4>This project aims to evaluate the efficacy of an unguided, web-based brief intervention (BI) incorporating genetic cancer-risk education to reduce alcohol consumption in a randomized controlled trial.<h4>Methods</h4>Participants will be recruited online between March and July 2026 through a Japanese research panel company. The gene discussed is ALDH2; the disease is cancer.