Abstract
It has long been hypothesized that increasing heritability with age of cognitive and educational performance is partly attributable to evocative gene-environment correlation. However, this hypothesis has not been widely tested.
We addressed this gap by examining whether children's education polygenic scores (PGS
) were associated with maternal self-reported positive and literacy-focused parenting when children were 5 years old, and if evoked parenting differences mediated genetic effects on children's educational outcomes (mother-reported at 6-8 years of age), while controlling for parental PGS
. We also investigated whether maternal reports of children's language at 5 years old were associated with parenting and mediated genetic effects on educational performance. These questions were addressed in a sample of 83,627 parent-offspring trios from the Norwegian Mother, Father and Child Cohort Study, a longitudinal population-based pregnancy cohort.
Children's PGS
were significantly associated with maternal literacy-focused (β = .03, 95% CI [0.01, 0.05], p = .021) but not positive parenting (β = 0.01, 95% CI [-0.02, 0.05], p = .410), and literacy-focused parenting significantly mediated the effects of children's PGS
on their educational performance (β = 0.01, 95% CI [1 × 10
, 0.01], p = .023). Children's language was associated with maternal parenting and mediated the effects of children's PGS
on their educational performance (β = 0.01, 95% CI [3 × 10
, 0.02], p = .002).
These findings support our hypotheses and suggest early language and parenting may be mechanisms implicated in the pathways from children's genetics to their educational outcomes.