Educational tracking and the polygenic prediction of education

Although it is well known that individuals’ genetics relate to their educational attainment, our understanding of how this may vary across differing educational institutional contexts is limited. In an educational system that does not separate students into different tracks early on, individuals’ unique skills and interests may have more time to manifest, which could potentially strengthen the genetic prediction of education. We test such a hypothesis exploiting the natural experiment of the Finnish comprehensive school reform employed gradually and regionally across the country between 1972 and 1977, using genetically informed population-representative surveys linked to data from administrative registers. We observed that the genetic prediction of education was stronger after the reform by one-third among men and those coming from low-educated families. We observed no evidence for reform effects among women or those from high-educated families. The increase in genetic prediction was particularly pronounced among the first cohort experiencing the new system. From the perspective of genetic prediction, the reform to a more universalist curriculum was successful in promoting equality of opportunity. The results also highlight the potential of various turbulent circumstances – such as puberty or ongoing restructuring of institutional practices – in magnifying genetic effects.