The Importance of Context in the Genetic Transmission of U.S. Party Identification

In this study, we discuss one example where behavior genetic findings vary greatly across political contexts. We present original findings on how party identification is heritable around the 2008 election on a sample of twins from Minnesota. As this is in contrast with findings from the late 1980s and with how a mid-2000 study interpreted their results, we explain how the increasing partisan ideological polarization could be responsible for these seemingly contradictory findings. In the Minnesota sample, we show a genetic correlation between party identification and ideology, a finding consistent in the political science literature. We highlight how heritability of political characteristics, like all others, is population specific and highly context dependent stressing its nondeterministic nature.