title: Genetic risk by experience interaction for childhood internalizing problems: converging evidence across multiple methods.
abstract: BACKGROUND
  Identifying how genetic risk interacts with experience to predict psychopathology is an important step toward understanding the etiology of mental health problems. Few studies have examined genetic risk by experience interaction (G×E) in the development of childhood psychopathology.
  
  
  METHODS
  We used both co-twin and parent mental health as markers of genetic risk to test whether G×E predicted internalizing problems in a sample of 8-year-old twins. Multi-instrument composites were used to characterize both parent and child psychopathology, and five experiential risk factors (socioeconomic status, single parent upbringing, negative parent-child interactions, number of negative life events, negative impact of negative life events) composed a cumulative risk index.
  
  
  RESULTS
  We found consistent evidence for G×E for child internalizing problems, with significant interaction effects emerging both when genetic risk was indexed by co-twin mental health and when it was based on parent mental health. When co-twin mental health was used to estimate genetic risk, child internalizing problems were more heritable for children at low rather than high experiential risk. When parent mental health was used to estimate genetic risk, the association between genetic risk and internalizing problems was stronger for children at elevated experiential risk. Consideration of the interaction effect sizes helps to reconcile these findings.
  
  
  CONCLUSIONS
  Our results suggest that the processes involved in both diathesis-stress and bioecological models of development may operate for child internalizing problems. Effect sizes indicated that the main effects of genetic and experiential risk were much better predictors of child internalizing problems than was their interaction.
authors.affiliation: University of Wisconsin-Madison, USA Arizona State University, USA.
authors.forename: Matthew K
authors.initials: MK
authors.lastname: Vendlinski
authors.forename: Kathryn
authors.initials: K
authors.lastname: Lemery-Chalfant
authors.forename: Marilyn J
authors.initials: MJ
authors.lastname: Essex
authors.forename: H Hill
authors.initials: HH
authors.lastname: Goldsmith
mesh_terms: D002648:Child; D002653:Child Behavior Disorders / Q000235:genetics* / Q000523:psychology*; D005260:Female; D020022:Genetic Predisposition to Disease; D006801:Humans; D007389:Internal-External Control; D008297:Male; D008603:Mental Health; D010287:Parent-Child Relations; D010290:Parents / Q000523:psychology*; D012307:Risk Factors; D011795:Surveys and Questionnaires; D014427:Twins / Q000235:genetics / Q000523:psychology*