Environmental and Genetic Influences on Developmental Outcomes Across the Domains of Language, Cognition, Motor Function, and Social Behavior.

Linguistic, motor, cognitive, and social-behavioral functions are fundamental facets of a child's neurodevelopment and are influenced by both genetic factors and environmental factors, such as the home environment, including the parents' mental health. However, the nature of these influences remains largely unknown. Using a genotyped cohort of 391 7-year-old children with comprehensive phenotype data on linguistic, motor, cognitive, and social-behavioral performance as well as data on parental mental health and the home environment, we performed regression analyses for the individual neurodevelopmental domains and principal components (PCs) capturing the variance across all domains simultaneously, where these outcomes were regressed on a polygenic score for educational attainment (PGS for EA) as a proxy for genetic factors and the Home Observation for Measurement of the Environment (HOME) as a proxy for environmental factors. HOME was significantly associated with all domains; the PGS for EA was nominally significantly associated (p ≤ 0.05) with cognitive function only. In the principal component analysis, PC1 and PC2 captured 52.57% and 20.73% of the variance in our phenotypic data, respectively. HOME was significantly associated only with PC1, while the PGS for EA was significantly associated only with PC2. Significant differences between familial risk groups were observed for PC1. Our results suggest an important role for potentially modifiable environmental factors on child neurodevelopment across multiple domains. We identified two orthogonal dimensions capturing parts of phenotypic variance that were associated with either environmental or genetic factors, but not both, providing insight into the interplay between genes and the environment in neurodevelopment.