title: Lack of association of DRD4 exon 3 VNTR genotype with reactivity to dynamic smoking cues in movies.
abstract: BACKGROUND
  The objective of the present study was first to examine whether dynamic smoking cues in movies trigger craving, and second to explore whether the DRD4 48 bp variable number of tandem repeat (VNTR) exon 3 genotype modifies this relationship. Using an experimental design, daily adult smokers were exposed to a movie segment in which either several characters smoked, or the smoking was completely edited out.
  
  
  METHODS
  In a human laboratory, that reflected a naturalistic setting, 112 daily smokers (mean age=22.45; SD=4.15) watched an edited version of the movie Alfie (2007). Saliva samples were collected for DNA isolation. Craving was assessed at 4 times: before and after the movie, and in two advertisement breaks during the movie.
  
  
  RESULTS
  The results did not indicate any evidence of a three-way interaction between movie condition, the DRD4 VNTR polymorphism and time and no evidence of a main effect of condition on craving. The results found evidence of a main effect of the DRD4 VNTR polymorphism on craving (p=.03), indicating that smokers carrying the DRD4 7-repeat allele showed higher levels of craving compared with smokers without the DRD4 7-repeat allele.
  
  
  CONCLUSIONS
  Dynamic smoking cues in movies do not affect smokers' craving and this is not modified by DRD4 genotype. Smokers carrying the DRD4 7-repeat allele developed higher levels of craving in the context of watching a movie than non-carriers. Due to the small sample size, these results need to be treated with caution.
authors.affiliation: Behavioural Science Institute, Radboud University Nijmegen, PO Box 9104, 6500 HE Nijmegen, The Netherlands. k.lochbuehler@pwo.ru.nl
authors.forename: Kirsten
authors.initials: K
authors.lastname: Lochbuehler
authors.forename: Maaike
authors.initials: M
authors.lastname: Verhagen
authors.forename: Marcus R
authors.initials: MR
authors.lastname: Munafò
authors.forename: Rutger C M E
authors.initials: RC
authors.lastname: Engels
mesh_terms: D000483:Alleles; D003463:Cues; D005091:Exons / Q000235:genetics; D005260:Female; D005838:Genotype; D006579:Heterozygote; D006801:Humans; D007062:Identification, Psychological; D008297:Male; D018598:Minisatellite Repeats / Q000235:genetics*; D009040:Motion Pictures; D050638:Receptors, Dopamine D4 / Q000235:genetics*; D012907:Smoking / Q000235:genetics* / Q000523:psychology*; D011795:Surveys and Questionnaires; D055815:Young Adult
chemical_list: C493599:DRD4 protein, human; D050638:Receptors, Dopamine D4
keywords: Craving; Cue reactivity; DRD4 VNTR polymorphism; Movie; Smoking