Political knowledge modifies the impact of innate predispositions on political ideology, according to new research published in the Journal of Experimental Political Science. The study provides evidence that political sophistication helps to transform genetic predispositions into strong and consistent ideological views.
Previous research has indicated that people have innate ideological predispositions. Other research, however, has indicated that coherent and potent ideological views are not the norm in the general public. To investigate this apparent contradiction, the authors of the new research examined responses from a database of American twins.
Comparisons between identical twins (who share all of their DNA) and fraternal twins (who share 50% of their DNA) allowed the researchers to estimate how much a specific trait was influenced by genes, a measure known as heritability.
“Research on biological influences on political attitudes really took off when I was in graduate school in the late 2000s,” explained study author Nathan P. Kalmoe, an associate professor in Louisiana State University’s Manship School of Mass Communication and the Department of Political Science. “I co-wrote a well-cited working paper about twin study methods for evaluating genetic influence on outcomes, but then I moved on to other things, including writing a book about the highly contingent nature of ideology in the general public.”
“I noticed that the biopolitics research seemed to imply everyone is ideological, while my survey research suggested it was limited to an informed minority. I saw an opportunity to integrate those seemingly conflicting sets of research. I teamed up with my dean and friend Martin Johnson, who was especially expert at the twin study methods we employed.”
For their study, the researchers examined data from 577 individuals in the Minnesota Twin Registry. Political knowledge was measured by asking the participants what portion of Congress votes to override a veto, which branch of government interprets the constitution, which branch nominates federal judges, what is the main duty of Congress, and which party is more conservative. The twins also completed an assessment of their cultural, political, and social attitudes.
Kalmoe and Johnson found that ideological views were highly heritable among the most knowledgeable participants, but significantly less heritable among the least knowledgeable participants.
“You need political knowledge to translate your general political tendencies into specific views,” Kalmoe told PsyPost. “Genes probably influence our politics indirectly, but it takes high levels of political knowledge for ordinary people to turn their liberal or conservative predispositions into a coherent set of liberal or conservative political attitudes. For the most knowledgeable twins in the study, genes accounted for 74% of their political views, while genes accounted for only 29% among the least knowledgeable half of twins.”
But just because political views are heritable does not mean that there is a “gene for liberalism” or a “gene for conservatism.”
“Twin study methods provide a general summary of genetic influence — they do not identify specific genes or mechanisms that explain how that influence takes place,” Kalmoe explained. “Those next steps are very difficult to undertake, but I expect political knowledge will continue to condition those steps toward realized ideology.”
“My co-author Martin died last fall a few days before this article was accepted for publication. He was a great leader, scholar, mentor, humanitarian, and friend. I will always miss him and be forever grateful for his great influence on my life and work,” Kalmoe added.
“We’re grateful to the National Science Foundation for supporting the survey costs for other scholars to field a politics-focused survey among Minnesota Twins and then make that data publicly available to everyone for analysis. More details on the study can be found here: https://www.unl.edu/polphyslab/data”
The study, “Genes, Ideology, and Sophistication“, was published March 8, 2021.