Immigrants often report lower rates of political participation compared to native majority members (Bird et al. 2011). In this paper, we synthesize arguments from the literatures on the intergenerational transmission of political participation and behavioral genetics to develop a more encompassing and thorough model explaining this gap in participation. Research using candidate gene studies (5HTT and MAOA) identified a plausible biological pathway by which genetic endowment increases the likelihood of individuals being more or less likely to engage in prosocial behavior such as political participation (Fowler and Dawes 2008; Edlin et al. 2007). At the same time, genetic studies demonstrate that environmental stress moderates gene expression leading to a higher prevalence of antisocial behavior. Immigrants tend to have more frequently stressful experience (Hovey 2000; e.g., due to experience of discrimination, language inadequacy, lack of social and financial resources), which may activate genes linked to antisocial behavior (including lower political participation rates). Hence, we expect that part of the political participation gap will be explained by systematic differences in the stressfulness of environment. Additionally, we argue that biological similarity within families contaminates prior research on intergenerational transmission patterns resulting in an overestimation of the extent to which transmission actually occurs (Jankowski 2007). We use multilevel models for extended family data to account for biological similarity to investigate patterns of intergenerational transmission. Our modeling strategy will focus on the question testing whether the extent to which the family environment is strained or stressful moderates direct transmission effects of parental political participation.