Interaction between novelty seeking and the aldehyde dehydrogenase 2 gene in heroin-dependent patients

OBJECTIVES: Heroin dependence is a multifactor disorder. We investigated the association of genetic factors and heroin-dependent temperaments to determine whether a temperament-gene interaction is involved in the pathogenesis of heroin dependence. METHODS: Three hundred seventy participants (259 heroin-dependent patients and 111 healthy controls) were recruited and finished the Tridimensional Personality Questionnaire to assess personality traits (temperament). The genotypes of the aldehyde dehydrogenase 2 (ALDH2) gene and the Val66Met polymorphism of the brain-derived neurotrophic factor (BDNF) gene using polymerase chain reactions plus restriction fragment length polymorphism analysis. RESULTS: Multiple logistic regression analysis showed significant main effects for novelty seeking (P ≤ 0.001) and harm-avoidance (P = 0.001) scores, and a significant interaction effect between novelty seeking and ALDH2 genotypes (P = 0.016) in heroin-dependent patients compared with controls. When stratified by the ALDH2 genotypes, only heroin-dependent patients with the *1*2 and *2*2 genotypes at ALDH2 had higher novelty-seeking scores than did controls (heroin dependence = 15.94, controls = 12.46; P ≤ 0.001). CONCLUSIONS: Our results provide initial evidence that the ALDH2 gene interacted with novelty seeking in heroin-dependent Han Chinese patients in Taiwan.