title: Role of p53, Mitochondrial DNA Deletions, and Paternal Age in Autism: A Case-Control Study.
abstract: The tumor suppressor p53 responds to a variety of environmental stressors by regulating cell cycle arrest, apoptosis, senescence, DNA repair, bioenergetics and mitochondrial DNA (mtDNA) copy number maintenance. Developmental abnormalities have been reported in p53-deficient mice, and altered p53 and p53-associated pathways in autism (AU). Furthermore, via the Pten-p53 crosstalk, Pten haploinsufficient-mice have autisticlike behavior accompanied by brain mitochondrial dysfunction with accumulation of mtDNA deletions.
  
  
  
  mtDNA copy number and deletions, and p53 gene copy ratios were evaluated in peripheral blood monocytic cells from children aged 2-5 years with AU (n = 66), race-, gender-, and age-matched typically neurodeveloping children (n = 46), and both parents from each diagnostic group, recruited by the Childhood Autism Risk from Genes and Environment study at the University of California, Davis.
  
  
  
  mtDNA deletions and higher p53 gene copy ratios were more common in children with AU and their fathers. The incidence of mtDNA deletions in fathers of children with AU was increased 1.9-fold over fathers of typically neurodeveloping children, suggesting a role for deficient DNA repair capacity not driven by paternal age. Deletions in mtDNA and altered p53 gene copy ratios seem to result from genetics (children with severity scores ≥8) and/or act in concert with environmental factors (children with 6-7 severity scores).
  
  
  
  Given pro- and antioxidant activities of p53, and associations of genomic instability with disorders other than AU, our study suggests a link between DNA repair capacity, genomic instability in the 17p13.1 region influenced by environmental triggers, and AU diagnosis.
authors.affiliation: Department of Molecular Biosciences, School of Veterinary Medicine.
authors.forename: Sarah
authors.initials: S
authors.lastname: Wong
authors.affiliation: Department of Molecular Biosciences, School of Veterinary Medicine.
authors.forename: Eleonora
authors.initials: E
authors.lastname: Napoli
authors.affiliation: Departments of Public Health Sciences and.
authors.forename: Paula
authors.initials: P
authors.lastname: Krakowiak
authors.affiliation: Biochemistry and Molecular Medicine, School of Medicine, and Medical Investigations of Neurodevelopmental Disorders (MIND) Institute, University of California Davis, Davis, California.
authors.forename: Flora
authors.initials: F
authors.lastname: Tassone
authors.affiliation: Departments of Public Health Sciences and Medical Investigations of Neurodevelopmental Disorders (MIND) Institute, University of California Davis, Davis, California.
authors.forename: Irva
authors.initials: I
authors.lastname: Hertz-Picciotto
authors.affiliation: Department of Molecular Biosciences, School of Veterinary Medicine, Medical Investigations of Neurodevelopmental Disorders (MIND) Institute, University of California Davis, Davis, California cgiulivi@ucdavis.edu.
authors.forename: Cecilia
authors.initials: C
authors.lastname: Giulivi
mesh_terms: D000328:Adult; D001321:Autistic Disorder / Q000175:diagnosis / Q000235:genetics*; D016022:Case-Control Studies; D002675:Child, Preschool; D004272:DNA, Mitochondrial / Q000235:genetics*; D005260:Female; D017353:Gene Deletion; D016158:Genes, p53 / Q000235:genetics*; D006801:Humans; D008297:Male; D010331:Paternal Age
chemical_list: D004272:DNA, Mitochondrial