A new study in the Journal of Politics by two University of California, San Diego political scientists, James Fowler and Christopher Dawes, finds that versions of two genes that moderate serotonin uptake in the brain have a substantial effect on whether or not an individual votes.
The researchers combined survey data from the National Longitudinal Study of Adolescent Health and genotype testing for variants of the MAOA and 5HTT genes. Researchers have found that MAOA and 5HTT exert a strong influence on the serotonin system regulating fear, trust, and social interaction. Fowler and Dawes report that people carrying the prosocial version of the MAOA gene were more likely to vote. The effect of the 5HTT gene on voting behavior was moderated by environmental influences. Specifically, people carrying the prosocial version of the 5HTT were not more likely to vote unless they were active in religious organizations. The researchers conclude:
By focusing on specific genes, our analysis is able to suggest potential causal pathways through which genes influence turnout. A significant body of research has found that the two genes we study, 5HTT and MAOA, influence social behavior via their impact on the serotonin metabolism and research within political science has identified prosociality as a significant determinant of turnout, thereby establishing a potential causal chain leading from these genes to observed political behavior. Again, we cannot test any causal pathway given our data so we are merely speculating based on previous work done in behavior genetics and political science.
More broadly, these results represent an important step for political science as a discipline. Specifically, they show that incorporating genetic information into our theories and analysis may contribute to a greater understanding of political behavior. The environment only approach used for so long in political science has frequently conceptualized human behavior as a ''blank slate'' on which any tendencies could be drawn, regardless of the unique biology of each individual. However, the results presented here refute the blank slate theory of political behavior. Although the environment is extremely important for turnout and other political acts, perhaps even more so than genes, we can no longer act as if genes do not matter at all. Genetic differences are likely to have important consequences for a whole range of political behaviors…
Even if one concedes genes do influence political behavior, it is tempting to assume that since they are not causally proximate to observed behaviors they can be safely ignored for practical purposes. However, this thinking is mistaken. Genes are the institutions of the human body-they constrain individual behavior just as political institutions constrain the behavior of groups of people. In this article we demonstrate that possessing a particular gene is associated with voting activity. Even after controlling for factors known to influence turnout, having a high MAOA allele raises the likelihood of voting by about 5%. Among people active in their religious organizations, having a long 5HTT allele raises the likelihood of voting by about 10%. We theorize that since low efficiency MAOA and 5HTT alleles limit the degree to which individuals are socially oriented, these alleles inhibit their desire or ability to participate in the political process…
Genes may also help us to explain two well known features of voting. First, parental turnout behavior has been shown to be one of the strongest predictors of turnout behavior in young adults. Although this has previously been interpreted as the result of social influence, the findings here suggest it may also be due to the inheritance of particular alleles of genes like MAOA and 5HTT. Second, turnout behavior has been shown to be habitual-the majority of people either always vote or always abstain. Scholars previously interpreted this as the result of reinforcement learning, but given that genes like MAOA and 5HTT are fixed, it might also be largely due to inherent genetic variability within the population.
Question: Are prosocial versions of these genes more or less prevalent among libertarians?
Finally, I can't resist an oldie but goodie about voting: A pollster asks a little old lady for whom she plans to vote. She acerbically replies: "Vote! Vote! I never vote! It only encourages them."
Disclosure: I always vote, even when it hurts.
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