Language and Non-verbal Cognition are Early Developmental Markers of Genetic Influences on Academic Achievement

Academic achievement is heritable, but how genetic differences translate into academic outcomes remains unclear. Using data from the Millennium Cohort Study (n = 8,014, 50.07% male), we tested whether early language and non-verbal cognition mediate the association between educational attainment polygenic scores (EA-PGS) and later academic achievement. Language at age 3 mediated 10.54% of the association between EA-PGS and academic achievement at age 7, and non-verbal cognition at age 5 mediated 32.73%. A similar pattern was found for achievement at age 17, with language at age 3 mediating 6.85% and non-verbal cognition at age 5 accounting for 20.25%. Exploratory models indicate that the genetic associations through language and non-verbal cognition are independent. These findings suggest that early cognitive and language development are key pathways through which genetic differences influence long-term academic outcomes.