BACKGROUND: Genetic variations of the dopamine and opioid receptors could influence the response to methadone maintenance treatment (MMT). METHODS: We included 238 MMT patients according to their response to treatment and methadone dosing, along with 217 subjects without substance dependence. All were genotyped for polymorphisms of the dopamine D1, D2, micro-opioid and delta-opioid receptor genes. RESULTS: The polymorphisms of the micro-opioid (118A>G), delta-opioid (921T>C), dopamine D1 (DdeI) and D2 (TaqI A) receptor genes were not associated with response to MMT and methadone dosing, whereas an association was found with the dopamine D2 receptor (DRD2) 957C>T polymorphism. The 957CC carriers were more frequently non-responders to treatment (OR=2.4; p=0.02) and presented a fourfold shorter period of negative urine screening (p=0.02). No significant differences in allele frequencies were observed between the MMT patients and the control group, suggesting no association of the analyzed polymorphisms with opioid dependence. CONCLUSIONS: These results suggest that DRD2 genotype may contribute to the understanding of the interindividual variability to the response to MMT.
BACKGROUND: Genetic variations of the dopamine and opioid receptors could influence the response to methadone maintenance treatment (MMT). METHODS: We included 238 MMTpatients according to their response to treatment and methadone dosing, along with 217 subjects without substance dependence. All were genotyped for polymorphisms of the dopamine D1, D2, micro-opioid and delta-opioid receptor genes. RESULTS: The polymorphisms of the micro-opioid (118A>G), delta-opioid (921T>C), dopamine D1 (DdeI) and D2 (TaqI A) receptor genes were not associated with response to MMT and methadone dosing, whereas an association was found with the dopamine D2 receptor (DRD2) 957C>T polymorphism. The 957CC carriers were more frequently non-responders to treatment (OR=2.4; p=0.02) and presented a fourfold shorter period of negative urine screening (p=0.02). No significant differences in allele frequencies were observed between the MMTpatients and the control group, suggesting no association of the analyzed polymorphisms with opioid dependence. CONCLUSIONS: These results suggest that DRD2 genotype may contribute to the understanding of the interindividual variability to the response to MMT.
Authors: Huaiyu Mi; Paul D Thomas; Huijun Z Ring; Ruhong Jiang; Katrin Sangkuhl; Teri E Klein; Russ B Altman Journal: Pharmacogenet Genomics Date: 2011-06 Impact factor: 2.089
Authors: Richard C Crist; Toni-Kim Clarke; Alfonso Ang; Lisa M Ambrose-Lanci; Falk W Lohoff; Andrew J Saxon; Walter Ling; Maureen P Hillhouse; R Douglas Bruce; George Woody; Wade H Berrettini Journal: Neuropsychopharmacology Date: 2013-04-23 Impact factor: 7.853
Authors: Richard Hallinan; Séverine Crettol; Kingsley Agho; John Attia; Jacques Besson; Marina Croquette-Krokar; Robert Hämmig; Jean-Jacques Déglon; Andrew Byrne; John Ray; Andrew A Somogyi; Chin B Eap Journal: Eur J Clin Pharmacol Date: 2009-07-29 Impact factor: 2.953