title: A functional variant of the serotonin transporter gene (SLC6A4) moderates impulsive choice in attention-deficit/hyperactivity disorder boys and siblings.
abstract: BACKGROUND
  Impulsive drive for immediate reward (IDIR) and delay aversion are dissociable elements of the preference for immediate over delayed rewards seen in attention-deficit/hyperactivity disorder (ADHD). We hypothesized that IDIR would be associated with dopamine regulating genes and delay aversion would be associated with serotonin-regulating genes.
  
  
  METHODS
  Impulsive drive for immediate reward and delay aversion were measured in 459 male children and adolescents (328 ADHD and 131 unaffected siblings) with a laboratory choice task. The sample was genotyped for the 5HTT (SLC6A4) promoter serotonin-transporter-linked polymorphic region polymorphism and a DAT1 (SLC6A3) 40-base pair variable number tandem repeat located in the 3'-untranslated region of the gene.
  
  
  RESULTS
  There was no effect of dopamine transporter (DAT)1 on IDIR. As predicted, serotonin-transporter-linked polymorphic region s-allele carriers were more delay averse. This effect was driven by the s/l genotype in the ADHD group. These results were not altered by taking account of the rs25531 A/G single nucleotide polymorphism and were independent of age, IQ, and oppositional defiant disorder symptoms.
  
  
  CONCLUSIONS
  The results support the genetic distinctiveness of IDIR and delay aversion in ADHD and implicate serotonin function in delay aversion. Possible explanations of the heterosis effect in the ADHD cases are presented.
authors.affiliation: Developmental Brain-Behaviour Laboratory, School of Psychology, University of Southampton, Southampton, United Kingdom. ejb3@soton.ac.uk
authors.forename: Edmund J S
authors.initials: EJ
authors.lastname: Sonuga-Barke
authors.forename: Robert
authors.initials: R
authors.lastname: Kumsta
authors.forename: Wolff
authors.initials: W
authors.lastname: Schlotz
authors.forename: Jessica
authors.initials: J
authors.lastname: Lasky-Su
authors.forename: Rafaela
authors.initials: R
authors.lastname: Marco
authors.forename: Ana
authors.initials: A
authors.lastname: Miranda
authors.forename: Fernando
authors.initials: F
authors.lastname: Mulas
authors.forename: Robert D
authors.initials: RD
authors.lastname: Oades
authors.forename: Tobias
authors.initials: T
authors.lastname: Banaschewski
authors.forename: Ueli
authors.initials: U
authors.lastname: Mueller
authors.forename: Penny
authors.initials: P
authors.lastname: Andreou
authors.forename: Hanna
authors.initials: H
authors.lastname: Christiansen
authors.forename: Isabel
authors.initials: I
authors.lastname: Gabriels
authors.forename: Henrik
authors.initials: H
authors.lastname: Uebel
authors.forename: Jonna
authors.initials: J
authors.lastname: Kuntsi
authors.forename: Barbara
authors.initials: B
authors.lastname: Franke
authors.forename: Jan
authors.initials: J
authors.lastname: Buitelaar
authors.forename: Richard
authors.initials: R
authors.lastname: Ebstein
authors.forename: Michael
authors.initials: M
authors.lastname: Gill
authors.forename: Richard
authors.initials: R
authors.lastname: Anney
authors.forename: Herbert
authors.initials: H
authors.lastname: Roeyers
authors.forename: Aribert
authors.initials: A
authors.lastname: Rothenberger
authors.forename: Joseph
authors.initials: J
authors.lastname: Sergeant
authors.forename: Hans Christoph
authors.initials: HC
authors.lastname: Steinhausen
authors.forename: Philip
authors.initials: P
authors.lastname: Asherson
authors.forename: Stephen V
authors.initials: SV
authors.lastname: Faraone
mesh_terms: D000293:Adolescent; D000483:Alleles; D001289:Attention Deficit Disorder with Hyperactivity / Q000235:genetics*; D002648:Child; D002755:Choice Behavior / Q000502:physiology*; D050483:Dopamine Plasma Membrane Transport Proteins / Q000235:genetics; D004328:Drive; D005838:Genotype; D006801:Humans; D007175:Impulsive Behavior / Q000235:genetics*; D008297:Male; D018598:Minisatellite Repeats; D012201:Reward; D050486:Serotonin Plasma Membrane Transport Proteins / Q000235:genetics*; D035781:Siblings
chemical_list: D050483:Dopamine Plasma Membrane Transport Proteins; D050486:Serotonin Plasma Membrane Transport Proteins