Genetic predictors of educational attainment and intelligence test performance predict voter turnout

The genetic variance that predicts educational attainment or intelligence test performance predicts individual-level voter turnout in a nationally representative sample and among people with psychiatric conditions, such as depression. Although the genetic influence on voter turnout is substantial (typically 40-50%), the underlying mechanisms remain unclear. Across the social sciences, research suggests that 'resources for politics' (as indexed notably by educational attainment and intelligence test performance) constitute a central cluster of factors that predict electoral participation. Educational attainment and intelligence test performance are heritable. This suggests that the genotypes that enhance these phenotypes could positively predict turnout. To test this, we conduct a genome-wide complex trait analysis of individual-level turnout. We use two samples from the Danish iPSYCH case-cohort study, including a nationally representative sample as well as a sample of individuals who are particularly vulnerable to political alienation due to psychiatric conditions (n = 13,884 and n = 33,062, respectively). Using validated individual-level turnout data from the administrative records at the polling station, genetic correlations and Mendelian randomization, we show that there is a substantial genetic overlap between voter turnout and both educational attainment and intelligence test performance.

Automated summary

Genetic variance predicting educational attainment or intelligence test performance also predicts individual-level voter turnout, with substantial genetic overlap between voter turnout and both educational attainment and intelligence test performance. Although genetic influence on voter turnout is significant, the underlying mechanisms are still unclear. Educational attainment and intelligence test performance are heritable, suggesting that genotypes enhancing these phenotypes could positively predict voter turnout.