title: Strong genetic contribution to peer relationship difficulties at school entry: findings from a longitudinal twin study.
abstract: This study assessed the genetic and environmental contributions to peer difficulties in the early school years. Twins' peer difficulties were assessed longitudinally in kindergarten (796 twins, Mage = 6.1 years), Grade 1 (948 twins, Mage = 7.1 years), and Grade 4 (868 twins, Mage = 10 years) through multiple informants. The multivariate results revealed that genetic factors accounted for a strong part of both yearly and stable peer difficulties. At the univariate level, the genetic contributions emerged progressively, as did a growing consensus among informants with respect to those who experienced peer difficulties. These results underline the need to intervene early and persistently, and to target the child and the peer context to prevent peer difficulties and their consequences.
authors.affiliation: Université Laval, Canada. michel.boivin@psy.ulaval.ca
authors.forename: Michel
authors.initials: M
authors.lastname: Boivin
authors.forename: Mara
authors.initials: M
authors.lastname: Brendgen
authors.forename: Frank
authors.initials: F
authors.lastname: Vitaro
authors.forename: Ginette
authors.initials: G
authors.lastname: Dionne
authors.forename: Alain
authors.initials: A
authors.lastname: Girard
authors.forename: Daniel
authors.initials: D
authors.lastname: Pérusse
authors.forename: Richard E
authors.initials: RE
authors.lastname: Tremblay
mesh_terms: D002648:Child; D005260:Female; D006801:Humans; D007398:Interpersonal Relations; D008137:Longitudinal Studies; D008297:Male; D010379:Peer Group; D012574:Schools; D012919:Social Behavior; D012931:Social Environment; D012934:Social Isolation; D013334:Students / Q000523:psychology; D014427:Twins / Q000235:genetics* / Q000523:psychology