title: Relation between food reinforcement and dopamine genotypes and its effect on food intake in smokers.
abstract: BACKGROUND
  Food reinforcement and dopaminergic activity may influence food consumption, but research on whether they interact has not been performed.
  
  
  OBJECTIVE
  We assessed the effects of food reinforcement and the interaction of food reinforcement with the dopamine transporter (SLC6A3) genotype and the dopamine D(2) receptor (DRD(2)) genotype on energy consumption.
  
  
  METHODS
  We studied food-consumption and reinforcing-value-of-food tasks in 88 smokers of European ancestry before they enrolled in smoking-cessation treatment. In the food-consumption task, subjects tasted and consumed 8 snack foods ad libitum. The reinforcing-value-of-food task assessed how hard subjects would work for food.
  
  
  RESULTS
  Significant interactions between dopamine genotypes and food reinforcement were observed. Subjects high in food reinforcement who lacked an SLC6A3*9 allele consumed significantly more calories (>150 kcal; P = 0.015) than did subjects low in food reinforcement or those high in food reinforcement who carried at least one SLC6A3*9 allele. Similarly, subjects high in food reinforcement who carried at least one DRD(2)*A1 allele consumed >130 kcal more (P = 0.021) than did subjects low in food reinforcement or those high in food reinforcement who lacked a DRD(2)*A1 allele. There was also a main effect of food reinforcement on energy intake (P = 0.005), with subjects high in food reinforcement consuming 104 kcal (or 30%) more than did subjects low in food reinforcement.
  
  
  CONCLUSIONS
  Food reinforcement has a significant effect on energy intake, and the effect is moderated by the dopamine loci SLC6A3 and DRD(2).
authors.affiliation: Departments of Pediatrics, School of Medicine and Biomedical Sciences, State University of New York at Buffalo, 14214-3000, USA. lhenet@buffalo.edu
authors.forename: Leonard H
authors.initials: LH
authors.lastname: Epstein
authors.forename: Suzanne M
authors.initials: SM
authors.lastname: Wright
authors.forename: Rocco A
authors.initials: RA
authors.lastname: Paluch
authors.forename: John J
authors.initials: JJ
authors.lastname: Leddy
authors.forename: Larry W
authors.initials: LW
authors.lastname: Hawk
authors.forename: Jodie L
authors.initials: JL
authors.lastname: Jaroni
authors.forename: Frances G
authors.initials: FG
authors.lastname: Saad
authors.forename: Susan
authors.initials: S
authors.lastname: Crystal-Mansour
authors.forename: Peter G
authors.initials: PG
authors.lastname: Shields
authors.forename: Caryn
authors.initials: C
authors.lastname: Lerman
mesh_terms: D000328:Adult; D000483:Alleles; D000704:Analysis of Variance; D016642:Bupropion / Q000627:therapeutic use; D003216:Conditioning, Operant; D004032:Diet; D004298:Dopamine / Q000235:genetics / Q000378:metabolism*; D050483:Dopamine Plasma Membrane Transport Proteins; D018765:Dopamine Uptake Inhibitors / Q000627:therapeutic use; D002149:Energy Intake / Q000235:genetics / Q000502:physiology*; D005260:Female; D005502:Food; D005838:Genotype; D006801:Humans; D008297:Male; D008562:Membrane Glycoproteins; D026901:Membrane Transport Proteins / Q000235:genetics*; D009419:Nerve Tissue Proteins / Q000235:genetics*; D011110:Polymorphism, Genetic; D017448:Receptors, Dopamine D2 / Q000235:genetics*; D012054:Reinforcement, Psychology; D012907:Smoking; D016540:Smoking Cessation
chemical_list: D050483:Dopamine Plasma Membrane Transport Proteins; D018765:Dopamine Uptake Inhibitors; D008562:Membrane Glycoproteins; D026901:Membrane Transport Proteins; D009419:Nerve Tissue Proteins; D017448:Receptors, Dopamine D2; C493214:SLC6A3 protein, human; D016642:Bupropion; D004298:Dopamine