Neither antisocial personality disorder nor antisocial alcoholism is associated with the MAO-A gene in Han Chinese males

Background: Recent studies on the genetics of alcoholism have suggested an association between antisocial alcoholism and the MAO-A gene. However, previous studies have failed to include subjects with antisocial personality disorder without alcoholism even though there is a high comorbidity between anti-social personality disorder and alcoholism. Consequently, the finding of an association between the MAO-A gene and alcoholism or antisocial personality disorder seems tenuous. In Taiwan, about 70% of the Han Chinese population have the ADH2*2 allele and 50% show ALDH2* I/*2 or ALDH2*2/*2 genotypes, which offer protection against drinking behavior and the risk of developing alcoholism. Thus, it is possible to recruit individuals with antisocial personality disorder but without alcoholism in Taiwan. Therefore, association studies of alcoholism or antisocial personality disorder in Chinese may be more reliable if pure antisocial alcoholics, pure antisocial personality disorders, and normal controls as MAO-A gene are examined. Methods: In this study, the associations among antisocial alcoholism, antisocial personality disorder, and the uVNTR and EcoRV polymorphisms of the MAO-A gene, both individually and as a haplotype, were investigated among male adults recruited from jails in Taipei. A total of 129 Chinese Han males were studied, including 41 with antisocial personality disorder with alcoholism, 50 with antisocial personality disorder but without alcoholism, and 38 without either disorder as a jail control group. The diagnoses of alcohol dependence and antisocial personality disorder were made according to DSM-IV criteria. In addition, 77 normal controls were collected from the community. Results: Strong linkage disequilibrium was found for the uVNTR and EcoRV variants of MAO-A gene in each study group. Conclusions: No significant association was observed between these two polymorphisms and antisocial personality disorder with alcoholism, either individually or for the haplotype, or for antisocial personality disorder without alcoholism. Thus, neither antisocial alcoholism nor antisocial personality disorder was associated with the genetic variants of MAO-A gene.