title: No evidence of association between Catechol-O-Methyltransferase (COMT) Val158Met genotype and performance on neuropsychological tasks in children with ADHD: a case-control study.
abstract: BACKGROUND
  Several studies have suggested an association between the functional Val158Met polymorphism in the Catechol-O-Methyltransferase (COMT) gene and neurocognitive performance. Two studies showed that subjects with the low activity Met allele performed better on the Wisconsin Card Sorting Test (WCST) and another study found an effect on processing speed and attention.
  
  
  METHODS
  We set out to examine the association between the Val158Met polymorphism and performance on neurocognitive tasks including those tapping working memory, attention and speed, impulsiveness and response inhibition in a sample of 124 children with ADHD. Task performance for each genotypic group was compared using analysis of variance.
  
  
  RESULTS
  There was no evidence of association with performance on any of the neurocognitive tasks.
  
  
  CONCLUSIONS
  We conclude that Val158Met COMT genotype is not associated with neurocognitive performance in our sample.
authors.affiliation: Department of Psychological Medicine, University of Wales College of Medicine, Cardiff, CF14 4XN, UK. millss1@cf.ac.uk
authors.forename: Sophie
authors.initials: S
authors.lastname: Mills
authors.forename: Kate
authors.initials: K
authors.lastname: Langley
authors.forename: Marianne
authors.initials: M
authors.lastname: Van den Bree
authors.forename: Eddy
authors.initials: E
authors.lastname: Street
authors.forename: Darko
authors.initials: D
authors.lastname: Turic
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 / Q000175:diagnosis* / Q000201:enzymology / Q000235:genetics*; D002394:Catechol O-Methyltransferase / Q000235:genetics*; D002648:Child; D005260:Female; D005838:Genotype; D006801:Humans; D008297:Male; D008715:Methionine / Q000235:genetics; D009483:Neuropsychological Tests / Q000706:statistics & numerical data; D011110:Polymorphism, Genetic; D012044:Regression Analysis; D013647:Task Performance and Analysis; D014633:Valine / Q000235:genetics
chemical_list: D008715:Methionine; D002394:Catechol O-Methyltransferase; D014633:Valine