Association of COMT Gene Polymorphisms with Response to Methadone Maintenance Treatment Among Chinese Opioid-Dependent Patients

Aim: To explore the association of the COMT gene polymorphisms (rs4680, rs737866, and rs933271) with the response to methadone maintenance treatment (MMT) among Chinese opioid-dependent patients. Methods: A total of 820 patients who were receiving MMT from Chinese clinics were recruited. Questionnaires were used to collect patient information, including sociodemographics, history of drug use, and stable methadone dosages. Three polymorphisms of COMT, rs4680, rs737866, and rs933271, were selected and genotyped using the Sequenom MassARRAY platform. Results: After adjusting for related factors including age, marital status, and methadone dosage, the genotype TC at rs933271 was demonstrated as the dominant difference between the MMT responsive group and nonresponsive group (p = 0.02, odds ratios [OR]: 1.57). In the dominant model of inheritance, the individuals carrying the TC or CC genotypes at rs933271 were more likely to respond to MMT than patients with the genotype TT (p = 0.02, OR: 1.53). No significant associations were observed between any of the allelic or genotypic variants of the rs4680 and rs737866 loci, and the response to MMT in this Chinese population. Patients with the haplotype A-T-A (rs737866-rs933271-rs4680) were more frequent in the nonresponsive group than in the responsive group (p < 0.05). Conclusion:COMT genetic variability is associated with the response to MMT.