The Genetic and Environmental Composition of Socioeconomic Status: A population-wide multi-method study in >170,000 Norwegian individuals

Depending on the measures, methods, and sample applied, estimated contributions of genetic and environmental factors to individual differences in SES vary substantially. In the current study we use register based measures of educational attainment, occupational prestige, income, and wealth, across four genotype and family-based heritability methods in the same population-wide sample consisting of >170,000 Norwegian parents aged 35-45. Education consistently had the highest heritability, followed by occupational prestige. Shared environmental contributions were particularly strong for educational attainment and wealth. The ‘missing heritability’ was prevalent between family- and individual-based designs. Multivariate covariance analysis revealed commonality in genetic and familial environmental factors, but not in individual-specific factors. As we minimize differences in estimates due to measurement error and sample characteristics, our study is a reliable and valid source for comparing methods and indicators and for assessing the commonality between genetic and environmental factors influencing individual differences in SES.