December 17, 2013
A research paper appearing in the academic journal Political Psychology re-affirms the genetic underpinnings of political beliefs, refuting critics who challenged previous research that linked politics with genetics.
The new paper, “Genetic and Environmental Transmission of Political Orientations,” is the lead article in the December edition of the journal. It is based upon a 2009 survey of nearly 600 sets of twins in their 50s and 60s, sought through the Minnesota Twin Registry.
“The data from the twin studies is strong enough now that if you don’t believe political attitudes and behaviors are genetically inherited, you can’t believe that breast cancer is genetically inherited and you can’t believe that addictions are genetically inherited,” said Kevin Smith, a University of Nebraska-Lincoln political scientist who co-authored the study.
The online publication includes a video featuring Smith explaining the study’s methodology and why comparing the political attitudes held by identical, or monozygotic, twins with those held by fraternal, or dizygotic, twins, demonstrates a genetic factor in political belief.
The reasoning behind a twins study is that pairs of twins share the same environment—they are reared by the same parents, in the same household, with the same socioeconomic and political influences. But monozygotic twins—who develop from the same fertilized egg—share 100 percent of their genetics, while dizygotic twins, who develop from separate fertilized eggs, share about half their genetics, like any other pair of siblings. Therefore, if monozygotic twins show a greater tendency to share political orientations than do dizygotic twins, that tendency can be attributed to genetics, not to environment.
Hibbing cautions that the latest study shows a genetic connection to general political orientations, which in turn influence a person’s stance on specific issues.
“Since it is not logical that genetics directly relates to highly specific political issues such as tax codes and school prayer, the recently published article constitutes an attempt to identify the broader orientations, such as authoritarianism and egalitarianism, that do connect to both genetics and specific issues.”
This is not the first time political scientists have studied twins to tease out whether political beliefs result from genetics.