The role of the ‘word gap’ in educational inequality: A genetically sensitive study

Differences in mothers’ vocabulary may help explain how educational inequality is transmitted across generations. In the E-Risk study—a longitudinal, nationally representative cohort of 1,116 British families—mothers’ educational attainment when children were 5 years old significantly predicted children’s educational attainment at age 18 (β = .33, 95% CI [.280, .371]). Using path models with polygenic scores, we disentangled genetic transmission (shared genetics) from environmentally mediated effects. We found that mothers’ vocabulary sophistication, derived from interview recordings when children were 5 years old, accounted for approximately 2% of the environmentally mediated influence on children’s educational outcomes. These findings support that the ‘word gap’—differences in children’s language learning opportunities—likely plays a small causal role in the intergenerational transmission of educational attainment. Our results highlight the importance of early language environments and may inform strategies aimed at reducing the impact of family background on educational inequality.