Neither single‐marker nor haplotype analyses support an association between the dopamine transporter gene and heroin dependence in Han Chinese

Abstract

Much evidence suggests that dysfunction of dopamine transporter-mediated dopamine transmission may be involved in the pathophysiology of substance abuse and dependence. The aim of this study was to examine whether the dopamine transporter gene (DAT1; SLC6A3) is associated with the development of heroin dependence (HD) and whether DAT1 influences personality traits in patients with HD. Polymorphisms of DAT1 were analyzed in a case-control study of 1046 Han Chinese (615 patients and 431 controls). All participants were screened using a Chinese version of the modified Schedule of Affective Disorder and SchizophreniaLifetime and all patients met the criteria for HD. Furthermore, a Chinese version of the Tridimensional Personality Questionnaire (TPQ) was used to assess personality traits in the patient group and examine the association between their personality traits and DAT1 polymorphisms. Of the patient group, 271 completed the TPQ. No statistically significant differences in allele or genotype frequencies of all investigated variants between HD patients and controls were observed. In haplotype analyses, four haplotype blocks of DAT1 were not associated with the development of HD. These DAT1 polymorphisms did not influence novelty seeking and harm avoidance scores in HD patients. This study suggests that the DAT1 gene may not contribute to the risk of HD and specific personality traits in HD among the Han Chinese population.

Association study of catechol-O-methyltransferase gene polymorphisms with schizophrenia and psychopathological symptoms in Han Chinese

“…Notably, population stratification issues may lead to a resetting of population gene frequencies, thereby causing a spurious association between a gene and a disease. It should be noted that our sample from Taiwan may not be representative of the entire Han Chinese population, because of a possible population stratification bias (Yeh et al 2010).…”

The dopamine transporter gene may not contribute to susceptibility and the specific personality traits of amphetamine dependence

“…Therefore, polymorphisms in the promoter region and 3 UTR represent good candidates in the context of linkage and association studies. Although the association between DAT1 and substance dependence has been examined previously (Franklin et al, 2009;Hong et al, 2003;Yeh et al, 2010), the role of DAT1 in the development of AD remains controversial and unclear. Prior studies on this topic have been limited to the investigation of only a few polymorphisms (Hamidovic et al, 2010;Hong et al, 2003;Ujike et al, 2003), and the limited results were unable to provide evidence of an existing association.…”

Polymorphisms of COMTVal158Metand DAT13′-UTR VNTRin Illicit Drug Use and Drug-Related Psychiatric Disorders

“…Like the COMT gene, the DAT1 polymorphism may cause varia-tions in dopamine transmission and contribute to individual differences in reward-seeking behavior (Dreher, Kohn, Kolachana, Weinberger, & Berman, 2009). However, the direct association between DAT1 3 -UTR VNTR and substance abuse has not been established in the literature (Bhaskar et al, 2012;Hou & Li, 2009;Yeh et al, 2010). The COMT Val158Met and DAT1 3 -UTR VNTR genotypes showed no significant effects on psychosis related to substance use (DIP).…”

“…This polymorphism has revealed associations with alcoholism (Bhaskar, Thangaraj, Wasnik, Singh, & Raghavendra Rao, 2012) and neurotoxicity effect of amphetamine (Giros, Jaber, Jones, Wightman, & Caron, 1996). However, the relationships between allele frequency of DAT1 3 -UTR VNTR and heroin dependence are unclear (Hou & Li, 2009;Yeh et al, 2010). Furthermore, little is known about whether the DAT1 3 -UTR VNTR contributes to the pathogenesis of drug-related psychiatric disorders.…”