Original ArticlesMu Opioid Receptor Gene (OPRM1) in Patients With Opiate Use DisorderMostafa, Nehal MBBCH, MSc; Mobasher, Maha W. MBBCH, MSc, MD; El Baz, Heba N. MBBCH, MSc, MD; Khalil, Mohamed A. MBBCH, MSc, MDAuthor Information Faculty of Medicine, Cairo University, Giza, Egypt The authors declare no conflict of interest. Correspondence to: Mohamed A. Khalil, MBBCH, MSc, MD, Faculty of Medicine, Cairo University, Giza 12311, Egypt (e-mails: [email protected]; [email protected]). Addictive Disorders & Their Treatment: March 2020 - Volume 19 - Issue 1 - p 16-21 doi: 10.1097/ADT.0000000000000174 Buy Metrics 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. Copyright © 2019 Wolters Kluwer Health, Inc. All rights reserved.