Mu Opioid Receptor Gene (OPRM1) in Patients With Opiate Use Disorder

Abstract

Introduction: Genetics of opiate dependence has focused on the opioidergic system, which is the primary target for opiates. Human mu opioid receptor (OPRM1) is the most important site for the analgesic effect of opioids. Methods: A case-control study included 40 patients with opiate use disorder and 40 matching control subjects. Polymorphism in Mu opioid receptor gene (OPRM1') was investigated in both patients and healthy controls by a genetic study. Substance use was further assessed in patients using the Addiction Severity Index while urine screen was required for controls. The single nucleotide polymorphisms (SNP) was reviewed in the SNP database of the National Centre for Biotechnology Information, and the life technologies SNP database. Results: No significant difference was found between the 2 groups (P=0.348) as regards the presence of polymorphic Mu opioid receptor gene (GT). There was no significant difference in the frequency of G and T alleles between the 2 groups; however, the frequency of G allele in cases was higher than T allele. No significant difference in group A between males and females as regarding gene type. Moreover, no difference was found in patients between the subjects who had GT and GG genotype regarding clinical data and severity of addiction and the occurrence of seizures. Conclusion: The use of opiates is associated with OPRM1 and the presence of the polymorphic gene (GT) has no relation with the different clinical characteristics of the opiate use.