MAOA-uVNTR Polymorphism May Modify the Protective Effect of ALDH2 Gene Against Alcohol Dependence in Antisocial Personality Disorder

Antisocial alcoholism is related to dopamine and serotonin which are catalyzed by monoamine oxidase A (MAOA) and acetaldehyde dehydrogenase 2 (ALDH2). The objective of this study is to determine whether the interaction between the MAOA and the ALDH2 genes is associated with subjects with antisocial personality disorder (ASPD) having alcoholism. A total of 294 Han Chinese men in Taiwan including 132 ASPD with alcoholism (Antisocial ALC) and 162 without alcoholism (Antisocial Non-ALC) were recruited in this study. Alcohol dependence and ASPD were diagnosed according to DSM-IV criteria. Genotypes of ALDH2 and MAOA-uVNTR were determined using PCR-RFLP. A significant difference of ALDH2 polymorphisms (p = 3.39E-05), but not of MAOA, was found among the 2 study groups. However, only after the stratification of the MAOA-uVNTR (variable number of tandem repeat located upstream) 3-repeat, a significant association between Antisocial Non-ALC and ALDH2*1/*2 or *2/*2 genotypes was shown (p = 1.46E-05; odds ratio = 3.913); whereas stratification of MAOA-uVNTR 4-repeat revealed no association. Multiple logistic regression analysis further revealed significant interaction of MAOA and ALDH2 gene in antisocial ALC (odds ratio = 2.927; p = 0.032). The possible interaction of MAOA and ALDH2 gene is associated with Antisocial ALC in Han Chinese males in Taiwan. However, the protective effects of the ALDH2*2 allele against alcoholism might disappear in subjects with ASPD and carrying MAOA-uVNTR 4-repeat allele in the Han Chinese male population.