Social and Genetic Pathways in Multigenerational Transmission of Educational Attainment

This study investigates the complex roles of the social environment and genes in the multigenerational transmission of educational attainment. Drawing on genome-wide data and educational attainment measures from the Framingham Heart Study (FHS) and the Health and Retirement Study (HRS), I conduct polygenic score analyses to examine genetic confounding in the estimation of parents' and grandparents' influences on their children's and grandchildren's educational attainment. I also examine social genetic effects (i.e., genetic effects that operate through the social environment) in the transmission of educational attainment across three generations. Two-generation analyses produce three important findings. First, about one-fifth of the parent-child association in education reflects genetic inheritance. Second, up to half of the association between parents' polygenic scores and children's education is mediated by parents' education. Third, about one-third of the association between children's polygenic scores and their educational attainment is attributable to parents' genotypes and education. Three-generation analyses suggest that genetic confounding on the estimate of the direct effect of grandparents' education on grandchildren's education (net of parents' education) may be inconsequential, and I find no evidence that grandparents' genotypes significantly influence grandchildren's education through non-biological pathways. The three-generation results are suggestive, and the results may change when different samples are used.