title: Prenatal unhealthy diet, insulin-like growth factor 2 gene (IGF2) methylation, and attention deficit hyperactivity disorder symptoms in youth with early-onset conduct problems.
abstract: Conduct problems (CP) and attention deficit hyperactivity disorder (ADHD) are often comorbid and have each been linked to 'unhealthy diet'. Early-life diet also associates with DNA methylation of the insulin-like growth factor 2 gene (IGF2), involved in fetal and neural development. We investigated the degree to which prenatal high-fat and -sugar diet might relate to ADHD symptoms via IGF2 DNA methylation for early-onset persistent (EOP) versus low CP youth.
  
  
  
  Participants were 164 youth with EOP (n = 83) versus low (n = 81) CP drawn from the Avon Longitudinal Study of Parents and Children. We assessed if the interrelationships between high-fat and -sugar diet (prenatal, postnatal), IGF2 methylation (birth and age 7, collected from blood), and ADHD symptoms (age 7-13) differed for EOP versus low CP youth.
  
  
  
  Prenatal 'unhealthy diet' was positively associated with IGF2 methylation at birth for both the EOP and low CP youth. For EOP only: (a) higher IGF2 methylation predicted ADHD symptoms; and (b) prenatal 'unhealthy diet' was associated with higher ADHD symptoms indirectly via higher IGF2 methylation.
  
  
  
  Preventing 'unhealthy diet' in pregnancy might reduce the risk of ADHD symptoms in EOP youth via lower offspring IGF2 methylation.
authors.affiliation: Centre for Child and Family Studies, Leiden University, Leiden, The Netherlands.|Department of Child and Adolescent Psychiatry/Psychology, Erasmus MC-University Medical Center Rotterdam, Rotterdam, The Netherlands.
authors.forename: Jolien
authors.initials: J
authors.lastname: Rijlaarsdam
authors.affiliation: Department of Psychology, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK.
authors.forename: Charlotte A M
authors.initials: CA
authors.lastname: Cecil
authors.affiliation: Department of Psychology, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK.
authors.forename: Esther
authors.initials: E
authors.lastname: Walton
authors.affiliation: Department of Psychology, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK.
authors.forename: Maurissa S C
authors.initials: MS
authors.lastname: Mesirow
authors.affiliation: Medical Research Council Integrative Epidemiology Unit, University of Bristol, Bristol, UK.
authors.forename: Caroline L
authors.initials: CL
authors.lastname: Relton
authors.affiliation: Medical Research Council Integrative Epidemiology Unit, University of Bristol, Bristol, UK.
authors.forename: Tom R
authors.initials: TR
authors.lastname: Gaunt
authors.affiliation: School of Social and Community Medicine, University of Bristol, Bristol, UK.
authors.forename: Wendy
authors.initials: W
authors.lastname: McArdle
authors.affiliation: Department of Psychology, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK.
authors.forename: Edward D
authors.initials: ED
authors.lastname: Barker
mesh_terms: D001289:Attention Deficit Disorder with Hyperactivity / Q000209:etiology*; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D019955:Conduct Disorder / Q000209:etiology*; D019175:DNA Methylation; D000070601:Diet, Carbohydrate Loading / Q000009:adverse effects*; D059305:Diet, High-Fat / Q000009:adverse effects*; D004739:England; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007335:Insulin-Like Growth Factor II / Q000378:metabolism*; D008297:Male; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects / Q000378:metabolism*
chemical_list: C035170:IGF2 protein, human; D007335:Insulin-Like Growth Factor II
keywords: 
  IGF2
  ; Avon Longitudinal Study of Parents and Children; DNA methylation; attention deficit hyperactivity disorder; conduct problems; diet