title: Functional effects of the DAT1 polymorphism on EEG measures in ADHD.
abstract: OBJECTIVE
  This paper examines whether dopamine transporter gene (DAT1) allele status mediates medication-related change in cognitive and neurophysiological measures among children with attention-deficiency/hyperactivity disorder (ADHD).
  
  
  METHODS
  A single 10-mg dose of methylphenidate was given in a double-blind, placebo-controlled fashion to children with ADHD who were seen for cognitive testing and EEG recording. Buccal samples were obtained and genotyped for the DAT1 polymorphism.
  
  
  RESULTS
  DAT1 allele status was associated with performance on a sustained attention task and medication-related EEG changes. Compared with those with one or more copies of the DAT1 9-repeat allele (9R), children with two copies of the 10-repeat allele (10R) exhibited poorer performance on the vigilance task. In addition, children with 10R exhibited medication-related EEG changes of increased central and parietal beta power, decreased right frontal theta power, and lower theta/beta ratios; 9R carriers showed the opposite pattern.
  
  
  CONCLUSIONS
  The data suggest that the DAT1 polymorphism mediates medication-related changes in cortical activity among children with ADHD.
authors.affiliation: Department of Psychiatry and Biobehavioral Sciences, UCLA-NPI, Los Angeles, USA. SLoo@mednet.ucla.edu
authors.forename: Sandra K
authors.initials: SK
authors.lastname: Loo
authors.forename: Elaine
authors.initials: E
authors.lastname: Specter
authors.forename: Andrew
authors.initials: A
authors.lastname: Smolen
authors.forename: Christian
authors.initials: C
authors.lastname: Hopfer
authors.forename: Peter D
authors.initials: PD
authors.lastname: Teale
authors.forename: Martin L
authors.initials: ML
authors.lastname: Reite
mesh_terms: D000293:Adolescent; D001289:Attention Deficit Disorder with Hyperactivity / Q000188:drug therapy / Q000235:genetics*; D000697:Central Nervous System Stimulants / Q000627:therapeutic use; D002648:Child; D003072:Cognition Disorders / Q000175:diagnosis; D050483:Dopamine Plasma Membrane Transport Proteins; D004311:Double-Blind Method; D004569:Electroencephalography; D005260:Female; D006801:Humans; D008297:Male; D008562:Membrane Glycoproteins; D026901:Membrane Transport Proteins / Q000235:genetics*; D008774:Methylphenidate / Q000627:therapeutic use; D009419:Nerve Tissue Proteins; D009483:Neuropsychological Tests; D011110:Polymorphism, Genetic / Q000235:genetics*
chemical_list: D000697:Central Nervous System Stimulants; D050483:Dopamine Plasma Membrane Transport Proteins; D008562:Membrane Glycoproteins; D026901:Membrane Transport Proteins; D009419:Nerve Tissue Proteins; C493214:SLC6A3 protein, human; D008774:Methylphenidate