Genetic influence on political interest is stronger in high-income families, highlighting a gene-environment interaction

A study published in Politics and the Life Sciences reveals that genetic predispositions to political interest manifest more strongly in adolescents from wealthier families.

Political engagement follows socioeconomic lines, with wealthier individuals generally displaying greater political interest. While previous research attributed these disparities primarily to childhood socialization, we now know that political interest and participation also have significant genetic components. This raises an intriguing question: Does family income create conditions that either amplify or suppress the expression of genetic predispositions toward political engagement?

Researchers Sebastian Jungkunz and Paul Marx analyzed data from the German TwinLife study, a comprehensive longitudinal project tracking genetic and environmental influences on various life outcomes. By comparing identical twins (who share 100% of their genetic material) with fraternal twins (who share approximately 50%), the researchers could isolate genetic effects from environmental factors.

The study included 6,174 individuals aged 10 to 29, with particular focus on adolescents between 10 and 18 years old—a critical period for the development of political identity.

Participants from diverse socioeconomic backgrounds rated their political interest on a 4-point scale. To ensure fair comparisons across different household compositions, the researchers used equivalized household income, which adjusts for family size. This methodological approach allowed them to estimate the relative contributions of genetic predispositions, shared family environment, and unique individual experiences to political interest.

A separate analysis focusing on early adults (aged 23 and older) controlled for genetic and family background factors to determine whether personal income during early adulthood independently affected political interest beyond these inherited traits.

The results revealed that genetic factors account for approximately 30-40% of the variation in political interest among adolescents. However, this genetic effect was not uniform across socioeconomic strata. In wealthier households, genetic influences played a much more prominent role in shaping political interest, while in less affluent families, these genetic effects were reduced.

In low-income environments, political interest appeared to be shaped more by external circumstances, such as family dynamics or economic stress, rather than by inherent predispositions. This suggests that economic hardship may constrain the expression of genetic tendencies toward political engagement.

Notably, when examining early adults, the researchers found that personal income in adulthood had no significant effect on political interest once genetic and family background factors were controlled for. This indicates that the connection between income and political engagement is largely established during adolescence rather than being a direct product of financial circumstances in adulthood.

While the twin-based methodology provides valuable insights into the link between genetics and environment, it is worth noting that twin samples may not perfectly represent the general population.

Rather than viewing political engagement as solely determined by either nature or nurture, this research highlights their interaction—genetic tendencies toward political interest require supportive environments to flourish.

These findings have important implications for understanding and addressing political inequality. Policymakers might develop more effective approaches to fostering civic participation across socioeconomic divides.

The study, “Parental Income Moderates the Influence of Genetic Dispositions on Political Interest in Adolescents,” was authored by Sebastian Jungkunz and Paul Marx.