Genetic influences on educational achievement in comparative perspective
European Sociological Review (2022), accepted
There is a growing interest in how social conditions moderate genetic influences on education (gene-environment interactions (GxE)). Previous research has focused on the family, specifically parents’ social background, and has neglected the institutional environment. To assess the impact of macro-level influences we compare genetic influences on educational achievement and their social stratification across Germany, Norway, Sweden, and the US. We combine well-established GxE-conceptualizations with the comparative stratification literature and propose that educational systems and welfare state regimes affect the realization of genetic potential. We analyze population-representative survey data on twins (Germany and the US) and twin registers (Norway and Sweden), and estimate genetically sensitive variance decomposition models. Our comparative design yields three main findings. First, Germany stands out with comparatively weak genetic influences on educational achievement suggesting that early tracking limits the realization thereof. Second, in the US genetic influences are comparatively strong and similar in size to the Nordic countries. Third, in Sweden genetic influences are stronger among disadvantaged families supporting the expectation that challenging and uncertain circumstances promote genetic expression. That we observe this pattern only in Sweden indicates that the underlying processes cannot be linked to institutional features that do not vary between Norway and Sweden.
Keywords: Germany, Norway, Sweden, USA, genetics