ALDH2 status, alcohol expectancies, and alcohol response: Preliminary evidence for a mediation model

Background: A genetic variant in the alcohol-metabolizing enzyme (aldehyde dehydrogenase; ALDH2*2 allele), common in individuals of Asian heritage, ha s been associated with both physiologic response to alcohol and alcohol con sumption. Prior research has also demonstrated that those with ALDH2*2 alle les have lower positive alcohol expectancies than those without these allel es. This preliminary study was designed to test whether the level of respon se to alcohol is the mechanism by which ALDH2 status may affect alcohol exp ectancies. Methods: Data were collected from 32 Asian American college students (14 wo men and 18 men). By use of a randomized, double-blind design, participants were administered oral placebo and alcohol at separate laboratory sessions. Data included blood tests to establish ALDH2 status, questionnaire measure s of demographic information and alcohol expectancy, and several physiologi c measures collected after placebo and alcohol administration. Results: ALDH2 status was related to alcohol response measures for both men and women. ALDH2 status was also related to tension reduction expectancies for women and to expectancies for cognitive behavioral impairment for men. In the male sample, the ALDH2/expectancy relationship was fully explained by the level of response to alcohol. Conclusions: These results represent a first step in understanding the mech anisms by which genetic factors, such as ALDH2 status, can affect alcohol-r elated learning.