Challenging the utility of polygenic scores for social science: Environmental confounding, downward causation, and unknown biology

Abstract

The sociogenomics revolution is upon us, we are told. Whether revolutionary or not, sociogenomics is poised to flourish given the ease of incorporating polygenic scores (or PGSs) as ‘genetic propensities’ for complex traits into social science research. Pointing to evidence of ubiquitous heritability and the accessibility of genetic data, scholars have argued that social scientists not only have an opportunity but a duty to add PGSs to social science research. Social science research that ignores genetics is, some proponents argue, at best partial and likely scientifically flawed, misleading, and wasteful. Here, I challenge arguments about the value of genetics for social science and with it the claimed necessity of incorporating PGSs into social science models as measures of genetic influences. In so doing, I discuss the impracticability of distinguishing genetic influences from environmental influences due to non-causal gene-environment correlations, especially population stratification, familial confounding, and downward causation. I explain how environmental effects masquerade as genetic influences in PGSs, which undermines their raison d’être as measures of genetic propensity, especially for complex socially contingent behaviors that are the subject of sociogenomics. Additionally, I draw attention to the partial, unknown biology, while highlighting the persistence of an implicit, unavoidable reductionist genes versus environments approach. I argue that leaving sociopolitical and ethical concerns aside, the potential scientific rewards of adding PGSs to social science are few and greatly overstated and the scientific costs, which include obscuring structural disadvantages and cultural influences, outweigh these meager benefits for most social science applications.

Building causal knowledge in behavior genetics

“…We disagree that the problems with social science genetics are rooted in political orientation or limited to ethical issues and thus solved by publicly repudiating genetic determinism and recognizing context-dependency and gene-environment interactionism. Crucially, as I outlined in my target article, the problems are not just political but are conceptual (e.g., Burt, 2023;, methodological Morris, Davies, Hemani, & Smith, 2020;Richardson & Jones, 2019), and biological (Crouch & Bodmer, 2020;McClellan & King, 2010).…”

“…The reality is nothing of the sort. 1 As I discuss at length in my target article, because of a host of limitations, current sociogenomics methodologies (i.e., genome-wide association studies [GWASs] and polygenic scores [PGSs]) are ill-suited for identifying specific "genes associated with" complex highly polygenic outcomes (Burt, 2023;Charney, 2022;.…”

The IT of Demography

“…Their use in clinical and research settings (both biomedical and social) therefore threatens to perpetuate existing outcome disparities between differently-racialized groups [44]. Even among individuals with exclusively European ancestry, however, PGS capture only one source of genetic heterogeneity (SNPs), and they are irremediably confounded by environmental and social factors [9]. This is particularly true of PGS for social outcomes, such as educational attainment, or socially motivated behaviors, such as smoking [18].…”

Genomics might not be the solution, but epistemic validity remains a challenge in the social sciences

“…In a detailed and compelling synthesis, Burt (2022) questions the validity of genomics to gain knowledge about social science issues. Burt's cautionary note is a much-needed reminder of the limitations of sociogenomics, a field that has seen a fair amount of hype in the last few years.…”

“…Despite the potential for sociogenomics in this space, tangible progress remains dependent on addressing current limitations in the use of polygenic scores, especially issues such as confounding and stratification (Burt, 2022). Though these limitations might be alleviated in the context of interventions due to the controlled nature of these designs, they generally remain issues that the field of sociogenomics will need to grapple with.…”