Childhood Socioeconomic Status and Polygenic Scores for Cognition Have Independent Associations with Cognitive Performance During Middle Childhood

Abstract

Childhood cognitive abilities are heritable and influenced by malleable environmental factors such as socioeconomic status (SES). As cognition and SES share genetic architecture, it is critical to understand the extent to which SES is associated with cognition beyond genetic propensity to inform the potential benefit of SES-based interventions. Previous investigations conducted in small samples have suggested that SES is linked with cognitive ability independent of polygenic prediction for educational attainment. Here, we extend this work to a large sample (total n = 4,650) of children (ages 9-10) of genomically-confirmed European ancestry. We find that an SES composite (i.e., family income-to-needs, caregiver education, and neighborhood median income) and a polygenic cognition score composite created using genomic structural equation modeling (COG PGS; Educational Attainment, Intelligence, and Executive Function) are associated with cognitive performance indices (i.e., general ability, executive function, learning/memory, fluid intelligence) that are largely independent of one another. SES x COG PGS interactions are not associated with cognition. These findings provide further evidence for the significant role of modifiable environmental factors in the development of cognitive abilities in youth.

Associations between Socioeconomic Status, Cognition, and Brain Structure: Evaluating Potential Causal Pathways Through Mechanistic Models of Development

“…Lastly, SES‐related and genetic influences on brain and behavior may have complex and sometimes nuanced relationships. Although there is evidence that SES‐related and genetic influences (the latter, for instance, as indexed by a polygenic score for educational attainment) may have independent contributions to variation in brain structure (Judd et al., 2020; Paul et al., 2021; Raffington et al., 2019), these studies and others indicate that the two influences may be correlated. This may occur either through population stratification or other forms of gene–environment correlation whereby, for example, children inherit genes from their parents and also experience the nurturing environment of their parents (itself influenced by the parents’ genetics).…”