title: Perceived Family Cohesion Moderates Environmental Influences on Prosocial Behavior in Nigerian Adolescent Twins.
abstract: Research shows that perceived family cohesion is positively related to prosocial behavior in adolescents. In this study, we investigated heritability of prosocial behavior (PB) and perceived family cohesion (FC) among Nigerian twins attending public schools in Lagos State, Nigeria (mean age = 14.7 years, SD = 1.7 years), and explored the issue of whether children's perception of cohesive family environment moderated genetic and environmental influences on (PB). The PB scale of the Strengths and Difficulties Questionnaire and the FC scale of the Family Adaptability and Cohesion Evaluation Scale III were completed by 2,376 twins (241 monozygotic (MZ) male, 354 MZ female, 440 dizygotic (DZ) male, 553 DZ female, and 788 opposite-sex DZ twins). A general sex-limitation and the bivariate genotype by environment interaction (G×E) models were applied to the data. The general sex-limitation model showed no significant sex differences, indicating that additive genetic and non-shared environmental influences were, 38% (95% CI = 31, 46) and 62% (95% CI = 54, 69) for PB and 33% (95% CI = 24, 40) and 67% (95% CI = 60, 76) for FC in both sexes. These estimates were similar to those found in Western and Asian twin studies to date. The correlation between PB and FC was 0.36. The best-fitting bivariate G×E model indicated that FC significantly moderated non-shared environmental influence unique to PB (E×E interaction). Specifically, non-shared environmental contributions to PB were highest when FC was lowest, and decreased as the levels of FC increased. However, genetic variances in PB were stable across all levels of FC. These findings suggest that FC reduces individual differences in PB by changing non-shared environmental experiences rather than genetic factors in PB.
authors.affiliation: Department of Education,Mokpo National University,Jeonnam,South Korea.
authors.forename: Yoon-Mi
authors.initials: YM
authors.lastname: Hur
authors.affiliation: Department of Psychology,Florida State University,Tallahassee,FL,USA.
authors.forename: Jeanette
authors.initials: J
authors.lastname: Taylor
authors.affiliation: Department of Education,Mokpo National University,Jeonnam,South Korea.
authors.forename: Hoe-Uk
authors.initials: HU
authors.lastname: Jeong
authors.affiliation: Department of Social Welfare,Mokpo National University,Jeonnam,South Korea.
authors.forename: Min-Seo
authors.initials: MS
authors.lastname: Park
authors.affiliation: Institute for Behavior Genetics,University of Colorado,Boulder,CO,USA.
authors.forename: Brett C
authors.initials: BC
authors.lastname: Haberstick
mesh_terms: D000293:Adolescent; D002648:Child; D005190:Family / Q000523:psychology*; D005260:Female; D059647:Gene-Environment Interaction; D005838:Genotype; D006801:Humans; D008297:Male; D012727:Sex Characteristics; D012919:Social Behavior; D014429:Twins, Dizygotic / Q000235:genetics* / Q000523:psychology; D014430:Twins, Monozygotic / Q000235:genetics* / Q000523:psychology
keywords: environment × environment interaction; family cohesion; gene × environment interaction; prosocial behavior; twins