The authors aimed to examine the association between the single-nucleotide polymorphism (SNP) C3435T (rs1045642) in the ABCB1 gene and opioid dependence (OD). Indeed, the authors aimed to explore the link between specific alleles of the SNP in the ABCB1 gene and the severity of OD.
Thirty patients with current OD divided as 15 patients with tramadol dependence, and 15 patients with heroin dependence were enrolled in the current study. The authors compared them to 15 healthy individuals. Patients were assessed through the International Classification of Diseases, 10th Revision (ICD-10) Symptom Checklist for mental disorders and the Addiction Severity Index (ASI). Participants were genotyped using real-time polymerized chain reaction and Taqman Master Mix.
With regard to the SNP C3435T (rs1045642) in the ABCB1 gene, there was a statistically significant difference between patients with OD and control group regarding homozygous CC genotype (P=0.02) and heterozygous CT genotype (P=0.04). The presence of SNP C3435T (rs1045642) raised the probability of tramadol dependence to 83%, compared with 27% in heroin dependence. Regarding the favorable and unfavorable alleles that predispose to opioid addiction; a statistically significant difference was found between patients with OD and control group regarding the non-CC allele (TT+CT) (P=0.03). Finally, there was a statistically significant difference between the psychological domain of ASI and the allele TT versus non-TT (CC and CT) (P=0.04, X2=5.8).
The SNP C3435T (rs1045642) in the ABCB1 gene might be implicated in OD, predominantly, tramadol dependence, suggesting that treatment strategies targeting this gene would reduce the risk for OD.