Association between norepinephrine transporter gene polymorphism and alcohol dependence in Japanese

Several studies have suggested that the norepinephrine transporter (NET) may play an important role in the pathogenesis of alcohol dependence. Therefore, in this study, we investigated whether the NET gene polymorphism is a susceptibility factor for alcohol dependence in 64 alcoholics and 73 healthy controls. In addition, we examined whether the combination of the NET and serotonin transporter genotypes are associated with alcohol dependence. The NET (1287G/A, -182T/C, and -3081A/T) and serotonin transporter (5-HTT3'UTR) genotypes were determined by the polymerase chain reaction (PCR)--restriction fragment length polymorphism (RFLP) method. No significant differences in genotype and allele frequencies of the NET and serotonin transporter gene polymorphisms were found between alcoholics and controls. The haplotype frequencies of the NET gene polymorphisms were not also significantly different between them. Furthermore, the combination of the NET and serotonin transporter genotypes had not significant effects on alcohol dependence. The present study suggests that the polymorphisms of 1287G/A, -182T/C and -3081A/T in NET gene are not.risk factors in alcohol dependence.