Association of the rs3864283 Polymorphism Located in the HINT1 Gene with Cigarette Use and Personality Traits

Nicotine is the major reinforcing component of tobacco and it is believed that the pharmacological effects of nicotine motivate the initiation and maintenance of a smoking habit. HINT1 appears to play a role in the modulation of the effects of drug abuse. Hence, the aim of this study was the analysis of the association between the rs3864283 polymorphism of the HINT1 gene and cigarette use; the analysis of personality traits assessed by the means of the NEO-FFI Inventory; the analysis of anxiety measured by the STAI questionnaire; and the analysis of the interactions between the rs3864283 and both personality traits and anxiety. The study group consisted of 522 volunteers. Of these, 371 were cigarette users and 151 were never-smokers. The genomic DNA was isolated from venous blood using standard procedures. The results of both inventories, i.e., NEO-FFI and STAI., were reported as the sten scores. Genotyping was conducted with the real-time PCR method. Statistically significant differences were found in the frequency of rs3864283 genotypes and alleles in the tested sample of Cigarette Users when compared to the control group. The Cigarette Users compared to the control group obtained higher scores in the assessment of NEO-FFI extraversion scale, and significantly lower results were obtained for the NEO-FFI openness scale, the agreeableness scale, and the conscientiousness scale. There was a statistically significant effect of rs3864283 genotype interaction and Cigarette Use or not using (control group) on the extraversion scale. There was also a statistically significant effect of Cigarette Users or the control group on the extraversion scale score. The results obtained in the presented study indicated a significant association between the HINT1 rs3864283 variant and smoking status. Moreover, this is the first study incorporating genetic association of above-mentioned polymorphic site with interaction analysis of personality traits and anxiety. Overall, the results of this study suggest that HINT1 is an important genetic component associated with nicotine usage mechanisms.