Integrating social science and genetics: news from the political front

The reductionism of genopolitics in the context of the relationships between biology and political science

The past two decades have seen an increase in the use of theories, data, assumptions and methods of the biological sciences in studying political phenomena. One of the approaches that combine biology with political science is genopolitics. The goal of the study was to analyse the basic ontological, methodological and epistemological assumptions for the reductionism of genopolitics. The results show that genopolitics assumes methodological reductionism but rejects ontological and epistemological reductionism. The key consequences of the findings are the irreducibility of political science to biology and the complementarity of genopolitical explanations and political science explanations based on culturalism. If my findings prove to be correct, they give rise to the formation of a hypothesis regarding the anti-reductionist orientation of the contemporary links between political science and biology. An important step towards confirming or falsifying such a hypothesis will be exploring the reductionism of contemporary biopolitical approaches such as neuropolitics or evolutionary political psychology.

Beyond culture and the family: Evidence from twin studies on the genetic and environmental contribution to values

Human values are abstract goals, affecting decisions, choices and behavior (Schwartz, 1992). Despite much value research, there is a lack of research on the etiology of values, specifically potential genetic influences. We therefore reviewed all published twin studies on human values, classified as representing four higher order values across two bipolar dimensions: Self-transcendence versus Self-enhancement and Openness to change versus Conservation. Across most studies, and most values, monozygotic twins correlated more strongly than dizygotic twins, indicating genetic contribution to values. Significant heritability estimates ranged from 24.5 to 85.7%. The effects of the environment shared by family members were generally weaker. Finally, there was a contribution of the non-shared environment for all values. After discussing the implications for the neuropsychological research on values, we suggest several future research directions, which may help guide the future science of the etiology of values. We also discuss the possible discrepancy between our findings and theory and research on value socialization and discuss the interplay of genes and the environment in the development of values.

Genes, psychological traits and civic engagement

Civic engagement is a classic example of a collective action problem: while civic participation improves life in the community as a whole, it is individually costly and thus there is an incentive to free ride on the actions of others. Yet, we observe significant inter-individual variation in the degree to which people are in fact civically engaged. Early accounts reconciling the theoretical prediction with empirical reality focused either on variation in individuals' material resources or their attitudes, but recent work has turned to genetic differences between individuals. We show an underlying genetic contribution to an index of civic engagement (0.41), as well as for the individual acts of engagement of volunteering for community or public service activities (0.33), regularly contributing to charitable causes (0.28) and voting in elections (0.27). There are closer genetic relationships between donating and the other two activities; volunteering and voting are not genetically correlated. Further, we show that most of the correlation between civic engagement and both positive emotionality and verbal IQ can be attributed to genes that affect both traits. These results enrich our understanding of the way in which genetic variation may influence the wide range of collective action problems that individuals face in modern community life.

Genetic and Environmental Parent-Child Transmission of Value Orientations: An Extended Twin Family Study

Despite cross-cultural universality of core human values, individuals differ substantially in value priorities, whereas family members show similar priorities to some degree. The latter has often been attributed to intrafamilial socialization. The analysis of self-ratings on eight core values from 399 twin pairs (ages 7-11) and their biological parents (388 mothers, 249 fathers; ages 26-65) allowed the disentanglement of environmental from genetic transmission accounting for family resemblance in value orientations. Results indicated that parent-child similarity is primarily due to shared genetic makeup. The primary source of variance in value priorities represented environmental influences that are not shared by family members. These findings do not provide evidence for parental influences beyond genetic influences contributing to intrafamilial similarity in value priorities.

The genetic and environmental foundations of political, psychological, social, and economic behaviors: a panel study of twins and families

Here we introduce the Genetic and Environmental Foundations of Political and Economic Behaviors: A Panel Study of Twins and Families (PIs Alford, Hatemi, Hibbing, Martin, and Smith). This study was designed to explore the genetic and environmental influences on social, economic, and political behaviors and attitudes. It involves identifying the psychological mechanisms that operate on these traits, the heritability of complex economic and political traits under varying conditions, and specific genetic correlates of attitudes and behaviors. In addition to describing the study, we conduct novel analyses on the data, estimating the heritability of two traits so far unexplored in the extant literature: Machiavellianism and Baron-Cohen's Empathizing Quotient.

The genetic and environmental roots of variance in negativity toward foreign nationals

This study quantified genetic and environmental roots of variance in prejudice and discriminatory intent toward foreign nationals and examined potential mediators of these genetic influences: right-wing authoritarianism (RWA), social dominance orientation (SDO), and narrow-sense xenophobia (NSX). In line with the dual process motivational (DPM) model, we predicted that the two basic attitudinal and motivational orientations-RWA and SDO-would account for variance in out-group prejudice and discrimination. In line with other theories, we expected that NSX as an affective component would explain additional variance in out-group prejudice and discriminatory intent. Data from 1,397 individuals (incl. twins as well as their spouses) were analyzed. Univariate analyses of twins' and spouses' data yielded genetic (incl. contributions of assortative mating) and multiple environmental sources (i.e., social homogamy, spouse-specific, and individual-specific effects) of variance in negativity toward strangers. Multivariate analyses suggested an extension to the DPM model by including NSX in addition to RWA and SDO as predictor of prejudice and discrimination. RWA and NSX primarily mediated the genetic influences on the variance in prejudice and discriminatory intent toward foreign nationals. In sum, the findings provide the basis of a behavioral genetic framework integrating different scientific disciplines for the study of negativity toward out-groups.

Genetic influences on political ideologies: twin analyses of 19 measures of political ideologies from five democracies and genome-wide findings from three populations

Almost 40 years ago, evidence from large studies of adult twins and their relatives suggested that between 30 and 60% of the variance in social and political attitudes could be explained by genetic influences. However, these findings have not been widely accepted or incorporated into the dominant paradigms that explain the etiology of political ideology. This has been attributed in part to measurement and sample limitations, as well the relative absence of molecular genetic studies. Here we present results from original analyses of a combined sample of over 12,000 twins pairs, ascertained from nine different studies conducted in five democracies, sampled over the course of four decades. We provide evidence that genetic factors play a role in the formation of political ideology, regardless of how ideology is measured, the era, or the population sampled. The only exception is a question that explicitly uses the phrase "Left-Right". We then present results from one of the first genome-wide association studies on political ideology using data from three samples: a 1990 Australian sample involving 6,894 individuals from 3,516 families; a 2008 Australian sample of 1,160 related individuals from 635 families and a 2010 Swedish sample involving 3,334 individuals from 2,607 families. No polymorphisms reached genome-wide significance in the meta-analysis. The combined evidence suggests that political ideology constitutes a fundamental aspect of one's genetically informed psychological disposition, but as Fisher proposed long ago, genetic influences on complex traits will be composed of thousands of markers of very small effects and it will require extremely large samples to have enough power in order to identify specific polymorphisms related to complex social traits.

The Influence of Major Life Events on Economic Attitudes in a World of Gene-Environment Interplay

The role of "genes" on political attitudes has gained attention across disciplines. However, person-specific experiences have yet to be incorporated into models that consider genetic influences. Relying on a gene-environment interplay approach, this study explicates how life-events, such as losing one's job or suffering a financial loss, influence economic policy attitudes. The results indicate genetic and environmental variance on support for unions, immigration, capitalism, socialism and property tax is moderated by financial risks. Changes in the magnitude of genetic influences, however, are temporary. After two years, the phenotypic effects of the life events remain on most attitudes, but changes in the sources of individual differences do not. Univariate twin models that estimate the independent contributions of genes and environment on the variation of attitudes appear to provide robust baseline indicators of sources of individual differences. These estimates, however, are not event or day specific. In this way, genetic influences add stability, while environment cues change, and this process is continually updated.

Overview of Behavioral Genetics Research for Family Researchers

This article provides an overview of the methods, assumptions, and key findings of behavioral genetics methodology for family researchers with a limited background. We discuss how family researchers can utilize and contribute to the behavioral genetics field, particularly in terms of conducting research that seeks to explain shared environmental effects. This can be done, in part, by theoretically controlling for genetic confounds in research that seeks to determine cause-and-effect relationships among family variables and individual outcomes. Gene-environment correlation and interaction are especially promising areas for the family researcher to address. Given the methodological advancements in the field, we also briefly comment on new methods in molecular genetics for studying psychological mental health disorders.

Gene-Environment Interplay in Twin Models

In this article, we respond to Shultziner's critique that argues that identical twins are more alike not because of genetic similarity, but because they select into more similar environments and respond to stimuli in comparable ways, and that these effects bias twin model estimates to such an extent that they are invalid. The essay further argues that the theory and methods that undergird twin models, as well as the empirical studies which rely upon them, are unaware of these potential biases. We correct this and other misunderstandings in the essay and find that gene-environment (GE) interplay is a well-articulated concept in behavior genetics and political science, operationalized as gene-environment correlation and gene-environment interaction. Both are incorporated into interpretations of the classical twin design (CTD) and estimated in numerous empirical studies through extensions of the CTD. We then conduct simulations to quantify the influence of GE interplay on estimates from the CTD. Due to the criticism's mischaracterization of the CTD and GE interplay, combined with the absence of any empirical evidence to counter what is presented in the extant literature and this article, we conclude that the critique does not enhance our understanding of the processes that drive political traits, genetic or otherwise.

The genetics of politics: discovery, challenges, and progress

For the greater part of human history, political behaviors, values, preferences, and institutions have been viewed as socially determined. Discoveries during the 1970s that identified genetic influences on political orientations remained unaddressed. However, over the past decade, an unprecedented amount of scholarship utilizing genetic models to expand the understanding of political traits has emerged. Here, we review the 'genetics of politics', focusing on the topics that have received the most attention: attitudes, ideologies, and pro-social political traits, including voting behavior and participation. The emergence of this research has sparked a broad paradigm shift in the study of political behaviors toward the inclusion of biological influences and recognition of the mutual co-dependence between genes and environment in forming political behaviors.

The genetic architecture of economic and political preferences

Preferences are fundamental building blocks in all models of economic and political behavior. We study a new sample of comprehensively genotyped subjects with data on economic and political preferences and educational attainment. We use dense single nucleotide polymorphism (SNP) data to estimate the proportion of variation in these traits explained by common SNPs and to conduct genome-wide association study (GWAS) and prediction analyses. The pattern of results is consistent with findings for other complex traits. First, the estimated fraction of phenotypic variation that could, in principle, be explained by dense SNP arrays is around one-half of the narrow heritability estimated using twin and family samples. The molecular-genetic-based heritability estimates, therefore, partially corroborate evidence of significant heritability from behavior genetic studies. Second, our analyses suggest that these traits have a polygenic architecture, with the heritable variation explained by many genes with small effects. Our results suggest that most published genetic association studies with economic and political traits are dramatically underpowered, which implies a high false discovery rate. These results convey a cautionary message for whether, how, and how soon molecular genetic data can contribute to, and potentially transform, research in social science. We propose some constructive responses to the inferential challenges posed by the small explanatory power of individual SNPs.

Biology, ideology, and epistemology: how do we know political attitudes are inherited and why should we care?

Evidence that political attitudes and behavior are in part biologically and even genetically instantiated is much discussed in political science of late. Yet the classic twin design, a primary source of evidence on this matter, has been criticized for being biased toward finding genetic influence. In this article, we employ a new data source to test empirically the alternative, exclusively environmental, explanations for ideological similarities between twins. We find little support for these explanations and argue that even if we treat them as wholly correct, they provide reasons for political science to pay more rather than less attention to the biological basis of attitudes and behaviors. Our analysis suggests that the mainstream socialization paradigm for explaining attitudes and behaviors is not necessarily incorrect but is substantively incomplete.