title: Altered mRNA expression of monoaminergic candidate genes in the blood of children with attention deficit hyperactivity disorder and autism spectrum disorder.
abstract: OBJECTIVE
  In absence of objective clinical characteristics the identification of peripheral biomarkers in neuropsychiatric disorders is highly relevant for the diagnostic process and an individualized therapy. We analyzed mRNA-expression of monoaminergic candidate genes (DRD4, DRD5, TPH1) in peripheral tissue of patients with attention deficit hyperactivity disorder (ADHD) and autism spectrum disorders (ASD), highly comorbid with ADHD, searching for possible molecular markers for these disorders.
  
  
  METHODS
  mRNA was obtained from children and adolescents with ADHD (n = 51) and ASD (n = 26), diagnosed according to ICD-10 criteria, as well as healthy controls (n = 39). mRNA expression was determined via quantitative realtime PCR (qRT-PCR) from whole blood cells.
  
  
  RESULTS
  The concentrations of DRD4-mRNA in the whole blood were significantly lower in ADHD and ASD children (19 of 26 comorbid with ADHD) compared to healthy controls. ASD patients revealed a significantly decreased DRD5 mRNA expression in comparison to the two other groups.
  
  
  CONCLUSIONS
  Alterations in mRNA expression patterns provide further evidence for a relevant effect of the respective candidate genes in the pathophysiology of ADHD. Given their potential as biomarkers mRNA expression patterns may be useful tools in (differential-) diagnostic procedures of ADHD and ASD. Future studies may determine the sensitivity and specificity of these putative biomarkers in larger samples including further neuropsychiatric diagnoses.
authors: Hospital of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, University of Würzburg, Würzburg, Germany. taurines@kjp.uni-wuerzburg.de
authors: Regina
authors: R
authors: Taurines
authors: Edna
authors: E
authors: Grünblatt
authors: Martin
authors: M
authors: Schecklmann
authors: Christina
authors: C
authors: Schwenck
authors: Laura
authors: L
authors: Albantakis
authors: Lennart
authors: L
authors: Reefschläger
authors: Susanne
authors: S
authors: Walitza
authors: Tobias
authors: T
authors: Renner
authors: Manfred
authors: M
authors: Gerlach
authors: Johannes
authors: J
authors: Thome
authors: Marcel
authors: M
authors: Romanos
mesh_terms: D000293:Adolescent; D001289:Attention Deficit Disorder with Hyperactivity / Q000175:diagnosis / Q000235:genetics*; D002648:Child; D002659:Child Development Disorders, Pervasive / Q000175:diagnosis / Q000235:genetics*; D015897:Comorbidity; D005260:Female; D015870:Gene Expression / Q000235:genetics*; D056726:Genetic Association Studies; D005819:Genetic Markers / Q000235:genetics; D006801:Humans; D008297:Male; D012333:RNA, Messenger / Q000235:genetics*; D050638:Receptors, Dopamine D4 / Q000235:genetics*; D050641:Receptors, Dopamine D5 / Q000235:genetics*; D012016:Reference Values
chemical_list: D005819:Genetic Markers; D012333:RNA, Messenger; D050638:Receptors, Dopamine D4; D050641:Receptors, Dopamine D5