title: Psychopathy trait scores in adolescents with childhood ADHD: the contribution of genotypes affecting MAOA, 5HTT and COMT activity.
abstract: OBJECTIVE
  Psychopathy-related traits, especially those tapping the 'emotional dysfunction' aspect of psychopathy that is characterized by lack of emotional responsiveness, are thought to be of genetic origin, but molecular genetic studies are yet to be undertaken. Gene variants that affect COMT, MAOA and 5HTT activity have previously been linked to antisocial behaviour. The aims of this study were to test whether these gene variants are linked to psychopathy traits in attention-deficit hyperactivity disorder (ADHD).
  
  
  METHODS
  Adolescents were followed up 5 years after an initial diagnosis of ADHD. Psychopathy trait scores were assessed [total scores and 'emotional dysfunction' (also referred to as 'affective') scores] and the MAOA 30-bp variable number of tandem repeats, SLC6A4 44-bp insertion/deletion and COMT Val158Met variants were genotyped.
  
  
  RESULTS
  All three gene variants were associated with 'emotional dysfunction' scores. MAOA and 5HTT variants were associated with total psychopathy scores. The results were not explained by associated conduct disorder.
  
  
  CONCLUSIONS
  The results suggest that specific gene variants influence psychopathy traits in ADHD.
authors.affiliation: Department of Psychological Medicine and Neurology, School of Medicine, Cardiff University, Heath Park, Cardiff, UK.
authors.forename: Tom
authors.initials: T
authors.lastname: Fowler
authors.forename: Kate
authors.initials: K
authors.lastname: Langley
authors.forename: Frances
authors.initials: F
authors.lastname: Rice
authors.forename: Marianne B M
authors.initials: MB
authors.lastname: van den Bree
authors.forename: Kenny
authors.initials: K
authors.lastname: Ross
authors.forename: Lawrence S
authors.initials: LS
authors.lastname: Wilkinson
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Owen
authors.forename: Michael C
authors.initials: MC
authors.lastname: O'Donovan
authors.forename: Anita
authors.initials: A
authors.lastname: Thapar
mesh_terms: D000293:Adolescent; D001289:Attention Deficit Disorder with Hyperactivity / Q000235:genetics / Q000523:psychology*; D002394:Catechol O-Methyltransferase / Q000235:genetics / Q000378:metabolism*; D005838:Genotype; D006801:Humans; D008995:Monoamine Oxidase / Q000235:genetics / Q000378:metabolism*; D050486:Serotonin Plasma Membrane Transport Proteins / Q000235:genetics / Q000378:metabolism*
chemical_list: C493230:SLC6A4 protein, human; D050486:Serotonin Plasma Membrane Transport Proteins; D008995:Monoamine Oxidase; D002394:Catechol O-Methyltransferase