A Longitudinal Analysis of Gene x Environment Interaction on Verbal Intelligence Across Adolescence and Early Adulthood

Behav Genet. 2023 Jul;53(4):311-330. doi: 10.1007/s10519-023-10145-y. Epub 2023 May 12.

Abstract

The Scarr-Rowe hypothesis proposes that the heritability of intelligence is higher in more advantaged socioeconomic contexts. An early demonstration of this hypothesis was Rowe and colleagues (Rowe et al., Child Dev 70:1151-1162, 1999), where an interaction between the heritability of verbal intelligence and parental education was identified in adolescent siblings in Wave I of the National Longitudinal Study of Adolescent to Adult Health. The present study repeated their original analysis at Wave I using contemporary methods, replicated the finding during young adulthood at Wave III, and analyzed the interaction longitudinally utilizing multiple measurements. We examined parental education, family income, and peer academic environment as potential moderators. Results indicated increased heritability and decreased shared environmental variance of verbal intelligence at higher levels of parental education and peer academic environment in adolescence. Moreover, moderation by peer academic environment persisted into adulthood with its effect partially attributable to novel gene-environment interactions that arose in the process of cognitive development.

Keywords: Academic environment; Cognitive development; Gene-environment interaction; Heritability; Socioeconomic status; Verbal intelligence.

MeSH terms

  • Adolescent
  • Adult
  • Educational Status
  • Gene-Environment Interaction*
  • Humans
  • Intelligence* / genetics
  • Longitudinal Studies
  • Parents
  • Young Adult