title: Developmental changes in genetic and environmental influences on Chinese child and adolescent anxiety and depression.
abstract: Twin and family studies using Western samples have established that child and adolescent anxiety and depression are under substantial genetic, modest shared environmental, and substantial non-shared environmental influences. Generalizability of these findings to non-Western societies remains largely unknown, particularly regarding the changes of genetic and environmental influences with age. The current study examined changes in genetic and environmental influences on self-reported anxiety and depression from late childhood to mid-adolescence among a Chinese twin sample. Sex differences were also examined.
  
  
  
  Self-reported anxiety and depression were collected from 712 10- to 12-year-old Chinese twins (mean = 10.88 years, 49% males) and again 3 years later. Quantitative genetic modeling was used to examine developmental changes in genetic and environmental influences on anxiety and depression, and sex differences.
  
  
  
  Heritability of anxiety and depression in late childhood (23 and 20%) decreased to negligible in mid-adolescence, while shared environmental influences increased (20 and 27% to 57 and 60%). Shared environmental factors explained most of the continuity of anxiety and depression (75 and 77%). Non-shared environmental factors were largely time-specific. No sex differences were observed.
  
  
  
  Shared environmental influences might be more pronounced during the transition period of adolescence in non-Western societies such as China. Future research should examine similarities and differences in the genetic and environmental etiologies of child and adolescent internalizing and other psychopathology in development between Western and non-Western societies.
authors.affiliation: Department of Psychology,Simon Fraser University,Burnaby,BC,Canada.
authors.forename: Y
authors.initials: Y
authors.lastname: Zheng
authors.affiliation: MRC Social, Genetic & Developmental Psychiatry Centre,Institute of Psychiatry, Psychology and Neuroscience, King's College London,De Crespigny Park,London,UK.
authors.forename: F
authors.initials: F
authors.lastname: Rijsdijk
authors.affiliation: MRC Social, Genetic & Developmental Psychiatry Centre,Institute of Psychiatry, Psychology and Neuroscience, King's College London,De Crespigny Park,London,UK.
authors.forename: J-B
authors.initials: JB
authors.lastname: Pingault
authors.affiliation: Department of Psychology,Simon Fraser University,Burnaby,BC,Canada.
authors.forename: R J
authors.initials: RJ
authors.lastname: McMahon
authors.affiliation: Department of Preventive Medicine,University of Southern California,Los Angeles,CA,USA.
authors.forename: J B
authors.initials: JB
authors.lastname: Unger
mesh_terms: D000293:Adolescent; D041923:Adolescent Development / Q000502:physiology*; D001007:Anxiety / Q000453:epidemiology / Q000209:etiology / Q000235:genetics; D002648:Child; D002657:Child Development / Q000502:physiology*; D002681:China / Q000453:epidemiology; D003863:Depression / Q000453:epidemiology / Q000209:etiology / Q000235:genetics; D005260:Female; D059647:Gene-Environment Interaction; D006801:Humans; D008297:Male
keywords: Adolescents; anxiety; depression; development; genetic influences; twins