Association of Galanin and Its Receptor Gene Polymorphism with Opioid Dependence: Preliminary Findings from India

Background: Genetic factors contribute to the development of opioid dependence syndrome (ODS), with evidence suggesting that the neuropeptide galanin, which plays a role in the stress response, may influence addiction risk through its receptor galanin receptor 1 (GALR1). However, this area is largely unexplored in the Indian context. Methods: This case-control study included 85 opioid-dependent patients and 85 healthy controls, all males, recruited from a tertiary care hospital in North India. All participants were assessed using a socio-demographic proforma, a case record form for substance use parameters, and the World Health Organization Alcohol, Smoking and Substance Involvement Screening Test (WHO-ASSIST) to assess harmful use of other substances. Participants were genotyped for polymorphisms in the galanin gene (GAL rs948854, rs3136541) and its receptor gene (GALR1 rs9807208). Results: The GAL rs3136541 and GALR1 rs9807208 polymorphisms showed significant differences in the genotypic distribution between cases and controls. The GALR1 rs9807208 minor allele (G) was associated with a 2.27-fold increased risk of opioid dependence (95% CI = 1.17–4.41; p = .01). However, no association was found between these polymorphisms and substance use patterns or related clinical parameters. Conclusions: This study provides preliminary evidence of an association between GALR1 rs9807208 polymorphism and opioid dependence in an Indian population, suggesting a potential genetic basis for addiction risk. Further studies with larger samples could be considered to confirm these findings and also to explore gene–environment interactions in opioid dependence.