Sven Oskarsson

The genetic origins of the relationship between psychological traits and social trust.

Recent studies have shown that trusting attitudes and behavior are biologically influenced. Focusing on the classic trust game, it has been demonstrated that oxytocin increases trust and that humans are endowed with genetic variation that influences their behavior in the game. Moreover, several studies have shown that a large share of the variation in survey responses to trust items is accounted for by an additive genetic component. Against this backdrop, this article makes two important contributions. First, utilizing a unique sample of more than 2,000 complete Swedish twin pairs, we provide further evidence of the heritability of social trust. Our estimates of the additive genetic component in social trust were consistent across the sexes -- .33 for males and .39 for females -- and are similar to the results reported in earlier studies. Secondly, we show that social trust is phenotypically related to three psychological traits -- extraversion, personal control, and intelligence - and that genetic factors account for most of these correlations. Jointly, these psychological factors share around 30% of the genetic influence on social trust both for males and females. Future studies should further explore the possible causal pathways between genes and trust using panel data on both psychological traits and social trust.

Power, Trust, and Institutional Constraints: Individual Level Evidence

This article focuses on how institutions matter in generating relationships of trust in an environment of unequal power. Trust is seen as the trusters expectation that the trustee will act trustworthily out of moral commitment and/or interest in continuing the relationship. Using cross-sectional data from a survey conducted in 2006 on Swedish employment relations the authors show that perceived power asymmetries between an employee and his or her superior have a negative impact on trust. However, perceptions about the enforcement and fairness of institutional constraints — rules for dismissal, conflict resolution, wage setting, and promotion — have conditioning effects. When the respondents perceive the rules as fair, trust is less influenced by increasing power asymmetries between an employee and his or her superior. The results have important implications. By designing institutions that are considered fair, distrust may be mitigated even in situations characterized by extensive power asymmetries.

Pre-Birth Factors, Post-Birth Factors, and Voting: Evidence from Swedish Adoption Data

This article analyzes a rich Swedish data set with information on the electoral turnout of a large sample of adoptees, their siblings, their adoptive parents, and their biological parents. We use a simple regression framework to decompose the parent-child resemblance in voting into pre-birth factors, measured by biological parents’ voting, and post-birth factors, measured by adoptive parents’ voting. Adoptees are more likely to vote if their biological parents were voters and if they were assigned to families in which the adoptive parents vote. We find evidence of interactions between the pre- and post-birth factors: the effect of the post-birth environment on turnout is greater amongst adoptees whose biological mothers are nonvoters. We also show that the relationships between parental characteristics, such as education, and child turnout, persist even in the absence of a genetic link between parent and child. The regression-based framework we utilize provides a basis for the integration of behavior-genetic research into mainstream political science.

Similarity vs. homogeneity: contextual effects in explaining trust

Diversity has powerful advantages, but may also generate internal tensions and low interpersonal trust. Despite extensive attention to these questions, the relationship between diversity and trust is often misunderstood and findings methodologically flawed. In this article, we specify two different mechanisms and adherent hypotheses. An individual might base her decision to trust on her perceived social similarity in relation to others in the community, that is, a similarity hypothesis. However, in a homogenous context, she might expect trustworthy behavior irrespective of her own social position due to signals of low degrees of social conflict and dense social networks, that is, a homogeneity hypothesis. Prior research has pinpointed only one of these mechanisms. The homogeneity hypothesis has not been explicated, and when the intention has been to test the similarity hypothesis, the homogeneity hypothesis has unintentionally been tested instead. The results are straightforward. While the homogeneity hypothesis is strongly supported, the findings speak against the similarity hypothesis.

Multi-trait analysis of genome-wide association summary statistics using MTAG

We introduce multi-trait analysis of GWAS (MTAG), a method for joint analysis of summary statistics from genome-wide association studies (GWAS) of different traits, possibly from overlapping samples. We apply MTAG to summary statistics for depressive symptoms (Neff = 354,862), neuroticism (N = 168,105), and subjective well-being (N = 388,538). As compared to the 32, 9, and 13 genome-wide significant loci identified in the single-trait GWAS (most of which are themselves novel), MTAG increases the number of associated loci to 64, 37, and 49, respectively. Moreover, association statistics from MTAG yield more informative bioinformatics analyses and increase the variance explained by polygenic scores by approximately 25%, matching theoretical expectations.MTAG is a new method for joint analysis of summary statistics from genome-wide association studies of different traits. Applying MTAG to summary statistics for depressive symptoms, neuroticism and subjective well-being increased discovery of associated loci as compared to single-trait analyses.

Gene discovery and polygenic prediction from a genome-wide association study of educational attainment in 1.1 million individuals.

Here we conducted a large-scale genetic association analysis of educational attainment in a sample of approximately 1.1 million individuals and identify 1,271 independent genome-wide-significant SNPs. For the SNPs taken together, we found evidence of heterogeneous effects across environments. The SNPs implicate genes involved in brain-development processes and neuron-to-neuron communication. In a separate analysis of the X chromosome, we identify 10 independent genome-wide-significant SNPs and estimate a SNP heritability of around 0.3% in both men and women, consistent with partial dosage compensation. A joint (multi-phenotype) analysis of educational attainment and three related cognitive phenotypes generates polygenic scores that explain 11–13% of the variance in educational attainment and 7–10% of the variance in cognitive performance. This prediction accuracy substantially increases the utility of polygenic scores as tools in research.Gene discovery and polygenic predictions from a genome-wide association study of educational attainment in 1.1 million individuals.

Why are Immigrants Underrepresented in Politics? Evidence from Sweden

Widespread and persistent political underrepresentation of immigrant-origin minorities poses deep challenges to democratic practice and norms. What accounts for this underrepresentation? Two types of competing explanations are prevalent in the literature: accounts that base minority underrepresentation on individual-level resources and accounts that emphasize political opportunity structures. However, due to the lack of data suitable for testing these explanations, existing research has not been able to adjudicate between these theories. Using registry-based microdata covering the entire Swedish adult population between 1991 and 2010 our study is the first to empirically evaluate these alternative explanations. We examine election outcomes to municipal councils over the course of six elections and find that variation in individual-level resources cannot explain immigrants’ underrepresentation. Further, when comparing immigrants and natives who face comparable political opportunity structures a large representation gap remains. Instead, we argue that discrimination by party gatekeepers plays a more significant role in perpetuating the underrepresentation of immigrants than do individual resources or structural variables.

MTAG: Multi- Trait Analysis of GWAS

We introduce Multi-Trait Analysis of GWAS (MTAG), a method for the joint analysis of summary statistics from GWASs of different traits, possibly from overlapping samples. We demonstrate MTAG using data on depressive symptoms (Neff = 354,862), neuroticism (N = 168,105), and subjective well-being (N = 388,538). Compared to 32, 9, and 13 genome-wide significant loci in the single-trait GWASs (most of which are novel), MTAG increases the number of loci to 74, 66, and 60, respectively. Moreover, the association statistics from MTAG yield more informative bioinformatics analyses and, consistent with theoretical calculations, improve prediction accuracy by approximately 25%.

Making Capitalism Work: Fair Institutions and Trust

This study tests three hypotheses on data from a survey on employment relations conducted in Sweden in 2006. The first hypothesis implies that the extent to which an employee perceives formal institutions as fair and duly enforced increases the probability that he/she will behave cooperatively. The second hypothesis states that an employees trust in the opposite party should have equivalent effects. The last hypothesis holds that an employees perception of formal institutions as fair and duly enforced increases his/her trust in the opposite party. All three hypotheses are supported by the data. The interpretation is that there is indeed an effect on cooperative behavior and willingness to enter into flexible contracts from perceptions of fair and enforced institutions, but it is indirect and mediated by attitudes of trust.

It Runs in the Family

What motivates citizens to run for office? Recent work has shown that early life parental socialization is strongly associated with a desire to run for office. However, parents not only shape their children’s political environment, they also pass along their genes to those same children. A growing area of research has shown that individual differences in a wide range of political behaviors and attitudes are linked to genetic differences. As a result, genetic factors may confound the observed political similarities among parents and their children. This study analyzes Swedish register data containing information on all nominated and elected candidates in the ten parliamentary, county council, and municipal elections from 1982 to 2014 for a large sample of adoptees and their adoptive and biological parents. By studying the similarity in political ambition within both adoptive and biological families, our research design allows us to disentangle so-called “pre-birth” factors, such as genes and pre-natal environment, and “post-birth” factors like parental socialization. We find that the likelihood of standing as a political candidate is twice as high if one’s parent has been a candidate. We also find that the effects of pre-birth and post-birth factors are approximately equal in size. In addition, we test a number of potential pre- and post-birth transmission mechanisms. First, disconfirming our expectations, the pre-birth effects do not seem to be mediated by cognitive ability or leadership skills. Second, consistent with a role modeling mechanism, we find evidence of a strong transmission in candidacy status between rearing mothers and their daughters.