title: Association of dopamine and opioid receptor genetic polymorphisms with response to methadone maintenance treatment.
abstract: 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.
authors.affiliation: Unité de Biochimie et de Psychopharmacologie Clinique, Centre de Neurosciences Psychiatriques, Département de Psychiatrie, Centre Hospitalier Universitaire Vaudois et Université de Lausanne, Hôpital de Cery, CH-1008 Prilly-Lausanne, Switzerland.
authors.forename: Séverine
authors.initials: S
authors.lastname: Crettol
authors.forename: Jacques
authors.initials: J
authors.lastname: Besson
authors.forename: Marina
authors.initials: M
authors.lastname: Croquette-Krokar
authors.forename: Robert
authors.initials: R
authors.lastname: Hämmig
authors.forename: Isabelle
authors.initials: I
authors.lastname: Gothuey
authors.forename: Martine
authors.initials: M
authors.lastname: Monnat
authors.forename: Jean-Jacques
authors.initials: JJ
authors.lastname: Déglon
authors.forename: Martin
authors.initials: M
authors.lastname: Preisig
authors.forename: Chin B
authors.initials: CB
authors.lastname: Eap
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D005260:Female; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006556:Heroin Dependence / Q000188:drug therapy* / Q000235:genetics* / Q000503:physiopathology; D006801:Humans; D008297:Male; D008691:Methadone / Q000008:administration & dosage*; D008875:Middle Aged; D009294:Narcotics / Q000008:administration & dosage*; D010597:Pharmacogenetics; D011110:Polymorphism, Genetic; D017448:Receptors, Dopamine D2 / Q000235:genetics*; D011957:Receptors, Opioid / Q000235:genetics*
chemical_list: D009294:Narcotics; D017448:Receptors, Dopamine D2; D011957:Receptors, Opioid; D008691:Methadone