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Introduction: Heroin dependence is a chronic relapsing disorder caused by a combination of genetic, epigenetic, and environmental factors. The genetic contribution in the vulnerability to heroin dependence is 40%-60%. Alterations in dopamine transport in the CNS are implicated in drug and alcohol dependence, and according to linkage studies, the HTR2A rs6313 single nucleotide polymorphism plays an important role in drug dependence and abuse. This case-control study aimed to investigate the association between HTR2A rs6313 and heroin dependence among a population from Northwest Iran.
Material & Methods: The study included a sample of 100 heroin-dependent patients and 102 control subjects. After DNA extraction from blood samples, the genotype of HTR2A rs6313 polymorphism was investigated among patients and controls using the PCR-RFLP method. The obtained data were analyzed in SPSS software to explore a significant association.
(Ethic code: 5/4/12152)
Findings: Frequencies of CC, CT, and TT genotypes were 23%, 50%, and 27% in the patient group and 32.35%, 44.12%, and 23.53% in the control group. According to statistical analysis, there were no significant differences between case and control groups in this regard (P>0.05).
Discussion & Conclusion: The results of the study could not support a significant association between HTR2A rs6313 polymorphism and heroin dependence in the Azeri population of Northwest Iran. This indicates the need to investigate other candidate genetic polymorphisms in the study population.