GWAS and cognitive abilities: Why correlations are inevitable and meaningless

Genomewide association studies (GWAS) are a relatively new and powerful tool to identify gene variants involved in human variation. The method scans the whole genome for small genetic variations—single nucleotide polymorphisms or SNPs—that correlate with differences in a particular trait, such as disease susceptibility or behavioral differences. GWAS have also looked for genetic variation related to cognitive ability test scores (CA) or educational attainments (EA). These aspirations have been thwarted by finding only small and usually non‐significant associations and failure to replicate the results. Recent studies claim to have overcome this problem by summating across large numbers, usually thousands, of the most promising weak effects identified from strength of association statistics into “polygenic scores” (PGS). Based on various tiers of statistical adjustments, some studies reported significant correlations between PGS and cognitive abilities [1], [2].

… such portents of social engineering based on genetic differences are conceptually simplistic and potentially misleading.

These publications have prompted proposals to address complex social and cognitive problems such as school performance or cognitive abilities based on genetic variation. Typical of the exuberance surrounding these GWAS/PGS findings is the suggestion that “recent results are a harbinger of future widespread use of PGS to predict genetic risk and resilience in the social and behavioral sciences” and even as a future basis for “personalized learning” in schools [2].

Here, I argue that such portents of social engineering based on genetic differences are conceptually simplistic and potentially misleading. First, there is already some cryptic but functionally irrelevant genetic stratification in human populations, which, quite likely, will covary with social stratification or social class. Second, this genetic stratification will correlate, adventitiously, with cognitive variation. Thirdly, the “dependent” variables (CA and EA) are themselves used to perpetuate social structure—and thereby the genetic structure—through social policy. …