title: The effects of nonshared environments on adolescent depression: findings from a sample of monozygotic twins.
abstract: OBJECTIVE
  Behavioral genetic research has revealed that nonshared environments are associated with depression and depressive symptomatology. Research examining specific nonshared environments related to adolescent depression remains relatively limited. To address this gap in the published data, we analyzed a sample of monozygotic (MZ) twin pairs from the National Longitudinal Study of Adolescent Health (Add Health) to examine the effects of nonshared environmental variables on adolescent depression.
  
  
  METHODS
  We used the MZ-twin-difference-scores method on data from MZ twins (n = 289 twin pairs) drawn from the Add Health to examine the effect of specific nonshared environments on adolescent depression.
  
  
  RESULTS
  Findings from the MZ-difference-scores analyses revealed that between-twin differences in maternal disengagement were significantly related to differences in adolescent depression. Additional analyses revealed that the association between adolescent depression and maternal disengagement was largely a child-driven effect.
  
  
  CONCLUSIONS
  Compared with previous research that has implicated maternal socialization in the development of depression among adolescents, the results of the current study revealed that differences in maternal socialization were a response and not a cause of adolescent depression.
authors.affiliation: College of Criminology and Criminal Justice, Florida State University, Tallahassee, Florida 32306-1127, USA.
authors.forename: Ryan T
authors.initials: RT
authors.lastname: Shields
authors.forename: Kevin M
authors.initials: KM
authors.lastname: Beaver
mesh_terms: D000293:Adolescent; D002648:Child; D003430:Cross-Sectional Studies; D003863:Depression / Q000175:diagnosis / Q000453:epidemiology / Q000235:genetics / Q000523:psychology*; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D010287:Parent-Child Relations; D016487:Parenting; D011569:Psychiatric Status Rating Scales; D011678:Punishment; D012931:Social Environment; D011795:Surveys and Questionnaires; D014430:Twins, Monozygotic / Q000523:psychology*; D014481:United States / Q000453:epidemiology