Prospective Cohort Study

Trust: The Social Virtues and the Creation of Prosperity

Most common human traits and diseases have a polygenic pattern of inheritance: DNA sequence variants at many genetic loci influence the phenotype. Genome-wide association (GWA) studies have identified more than 600 variants associated with human traits, but these typically explain small fractions of phenotypic variation, raising questions about the use of further studies. Here, using 183,727 individuals, we show that hundreds of genetic variants, in at least 180 loci, influence adult height, a highly heritable and classic polygenic trait. The large number of loci reveals patterns with important implications for genetic studies of common human diseases and traits. First, the 180 loci are not random, but instead are enriched for genes that are connected in biological pathways (P = 0.016) and that underlie skeletal growth defects (P < 0.001). Second, the likely causal gene is often located near the most strongly associated variant: in 13 of 21 loci containing a known skeletal growth gene, that gene was closest to the associated variant. Third, at least 19 loci have multiple independently associated variants, suggesting that allelic heterogeneity is a frequent feature of polygenic traits, that comprehensive explorations of already-discovered loci should discover additional variants and that an appreciable fraction of associated loci may have been identified. Fourth, associated variants are enriched for likely functional effects on genes, being over-represented among variants that alter amino-acid structure of proteins and expression levels of nearby genes. Our data explain approximately 10% of the phenotypic variation in height, and we estimate that unidentified common variants of similar effect sizes would increase this figure to approximately 16% of phenotypic variation (approximately 20% of heritable variation). Although additional approaches are needed to dissect the genetic architecture of polygenic human traits fully, our findings indicate that GWA studies can identify large numbers of loci that implicate biologically relevant genes and pathways.

Hundreds of variants clustered in genomic loci and biological pathways affect human height

Habits of the Heart Individualism and Commitment in American Life

Developmental Plasticity and Evolution. In: Mary Jane West-Eberhard, Editor, Oxford University Press (2003) Pp. xi+794. Price $50.00 paper.

Political scientists are making increasing use of the methodologies of behavior genetics in an attempt to uncover whether or not political behavior is heritable, as well as the specific genotypes that might act as predisposing factors for—or predictors of—political “phenotypes.” Noteworthy among the latter are a series of candidate gene association studies in which researchers claim to have discovered one or two common genetic variants that predict such behaviors as voting and political orientation. We critically examine the candidate gene association study methodology by considering, as a representative example, the recent study by Fowler and Dawes according to which “two genes predict voter turnout.” In addition to demonstrating, on the basis of the data set employed by Fowler and Dawes, that two genes do not predict voter turnout, we consider a number of difficulties, both methodological and genetic, that beset the use of gene association studies, both candidate and genome-wide, in the social and behavioral sciences.

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Candidate genes and political behavior

In an earlier article we challenged the findings of Fowler and Dawes (FD) that two genes predict voter turnout as part of a more general critique of “genopolitics.” FD now acknowledge that their finding of a “significant” direct association between MAOA and voting was incorrect, but claim to have replicated their finding of an “indirect” association between 5HTT, self-reported church attendance, and self-reported voting. We show that this finding is likely driven by population stratification and omitted variable bias. We then explain why, from the standpoints of genetics, neuroscience, and evolutionary biology, genopolitics is a fundamentally misguided undertaking; we also respond to FD's charge that some of our previous statements concerning genetics are “highly misleading,” “extremely disingenuous,” and “even incorrect.” We show that their criticisms demonstrate a lack of awareness of some basic principles in genetics and of discoveries in molecular genetics over the past 50 years.

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Genopolitics and the Science of Genetics

We would like to thank the Center for Business Ethics at Bentley University, which supported Tomas Baviera with a research fellowship from October 2012 to March 2013 during which he began working on this manuscript. Prof. Pamela Carpenter was extremely helpful in revising the early drafts of the text, and Prof. Jeffrey Moriarty provided invaluable comments on the final draft. Manuel Guillen is likewise thankful for the support of Bentley University's Center for Business Ethics, which has regularly hosted him as a visiting scholar, and for the support of the Real Colegio Complutense at Harvard University, where he worked on this manuscript as a research fellow in 2013 and 2014. Finally, we would like to thank our three anonymous reviewers whose feedback and insights dramatically improved the text.

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The Logic of Gift: Inspiring behavior in organizations beyond the limits of duty and exchange

We conduct an ultimatum game with three treatments: one in which endowments are earned through a real effort task (answering spelling questions under time pressure), one in which endowments are awarded through lotteries, and a standard ultimatum game with exogenously provided wealth. When subjects earn the money at stake, the modal response ceases to be an equal split, as proposals anchor around comparative earnings and these proposals are statistically different from those observed in the other treatments. Moreover, roughly half of lower earners propose keeping less than 50% of the pot for themselves. We argue that these results are best explained by Bicchieri’s account of norms and that equity, rather than equality, becomes the dominant norm in ultimatum bargaining when endowments are earned.

The origin of wealth matters: Equity norms trump equality norms in the ultimatum game with earned endowments

The inevitability and stability of liberal democracy is taken for granted in contemporary political discourse, although many of the architects of modern politics viewed democracies as fragile and prone to corruption and disintegration. A close look at the historical record reveals that a number of unique conditions enabled modern democratic states to be economically productive and socially cohesive - conditions that are not inevitable and which must be cultivated outside of the logic of democratic bargaining if the goods we associate with democratic governance are to resist corruption. Two of these conditions are paramount and warrant our attention more than ever today: first, a cultural commitment to “liberal ethics;” and, second, the ability to generate wealth without holding political power. When combined in the right way with democratic institutions these help explain the genius of western prosperity. However, democratic politics inherently generate forces that threaten to undermine these pillars of social cohesion and economic growth. In particular, democracy provides powerful incentives for rent seeking, grandstanding, and unsustainable borrowing. This paper explores the logics that give rise to these three phenomena, and further argues they are aggravated by complexity and the centralization of political power. The corrupting tendencies of democracy can be resisted, this paper concludes, through two principle means: investigative efforts that uncover and communicate abuses, and ideological commitments that limit the scope of political bargaining - both of which are necessary to preserve the “liberal” character of liberal democracies.

William English

Papers

Candidate genes and political behavior

Genopolitics and the Science of Genetics

The Logic of Gift: Inspiring behavior in organizations beyond the limits of duty and exchange

The origin of wealth matters: Equity norms trump equality norms in the ultimatum game with earned endowments

Institutional Corruption and the Crisis of Liberal Democracy