Association Between Personality Traits and ALDH2 Polymorphism in Japanese Male Alcoholics

Alcoholics who have developed alcoholism despite a strong negative risk factor, that is, the inactive form of aldehyde dehydrogenase-2 (ALDH2), are considered advantageous for studying predisposing factors for alcoholism. This study aimed to compare personality profiles and clinical characteristics between alcoholics with active and inactive ALDH2. Subjects were 460 male Japanese alcoholics hospitalized in Kurihama Alcoholism Center. All patients underwent Cloninger's Tridimensional Personality Questionnaire and semi-structured interviews 4 to 8 weeks after admission to obtain data on personalities and clinical characteristics. ALDH2 genotypes were determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Sixty-six patients had the inactive form of ALDH2 (ALDH2*1/2*2) and 394 had the active form (ALDH2*1/2*1). Alcoholics with inactive ALDH2 had significantly higher novelty-seeking (NS) and lower harm-avoidance (HA) scores compared with those with active ALDH2. The inactive ALDH2 group experienced delirium tremens significantly less frequently than the active ALDH2 group. These results suggest that high NS and low HA scores in alcoholics with inactive ALDH2 are associated with an increased risk for developing alcoholism, despite a low enzymatic ability to eliminate toxic acetaldehyde in these subjects. A study of alcoholics with inactive ALDH2 is useful for detecting environmental or personality factors related to alcoholism.