The transmission of family background inequality in education across four countries

Children show substantial differences in their learning ability even before entering school, which are largely due to their family background. Yet, little is known about the transmission of family background inequality in education across different school systems.

Here, we capitalised on data from TEDS, E-Risk, TwinLife, the Netherlands Twin Register, and the Minnesota Twin Family Study, five population-based twin family studies which collected data on twins’ school performance, their genotypes, and the family socioeconomic status (SES).

Using polygenic scores (PGS) for years of education (EA3), we first compared the prediction of school performance between the ages 7 to 16 years from SES and PGS across countries and education systems. In Germany and the Netherlands, students are selected in three-tiered secondary schools based on prior achievement, whereas the UK and US offer non-selective, comprehensive secondary education following a standard curriculum.

Second, we tested the predictiveness of PGS within and between families with control for SES. Thus, we investigated potential confounders of PGS prediction related to family shared factors (e.g., SES, population stratification, assortative mating), which elucidates contextual effects on the genetic and environmental transmission of family background inequality in education.