The Heterosis Effect in Human Capital and Wealth Accumulation

In genetics, heterosis refers to the phenomenon where crossbreeding within a species produces offspring with greater genetic fitness and superior phenotypic characteristics compared to their parents. We propose a novel socioeconomic heterosis hypothesis and examine whether genetic diversity at the individual level benefits economic success. Empirical results from UK Biobank (N=488,152) indicate that people with higher genome-wide heterozygosity perform better in modern societies. We find consistent, positive links with education, earnings, leadership, height, and ownership of a home and car; a one standard deviation increase in heterozygosity is associated with 0.75% higher income and modest gains in schooling and assets. Results hold with additional controls and Bonferroni correction for multiple hypothesis testing; no effects are found for migration, diabetes, or neuroticism. The relationship rises steadily across the observed range and is stronger for men, suggesting sexual selection in socioeconomic settings. Because heterozygosity is fixed at conception, our evidence points to an underappreciated endowment shaping human capital and wealth accumulation. The contribution is to introduce and document individual-level heterosis effects in economics, offering a new channel for inequality and socioeconomic outcomes.