This draft by Fowler, Baker and Dawes looks interesting. Here is the abstract:

The decision to vote has puzzled scholars for decades. Theoretical models predict little or no participation in large population elections and empirical models have typically explained only a relatively small portion of individual-level variance in turnout behavior. However, these models have not considered the influence of genetic variation on voting. Matching public voter turnout records in Los Angeles to a twin registry, we study the heritability of political behavior in monozygotic and dizygotic twins. The results show that the decision to vote is significantly
influenced by genetic factors. We also replicate these results with data from the National Longitudinal Study of Adolescent Health and show that they extend to a broad class of acts of political participation. Our findings suggest that humans exhibit genetic variation in their tendency to participate in political activities and, more importantly, that biological evolution may play an important role in the development of mechanisms that help humans overcome social dilemmas.