Genomic ancestry, cognitive ability, and socioeconomic outcomes

Abstract

Self-identified race/ethnicity (SIRE) groups are known to differ in average cognitive ability, socioeconomic status and genomic ancestry, but the causal paths are disputed. We used data from the Pediatric Imaging, Neurocognition, and Genetics Study (PING; n = 1,369) to examine the relationship between cognitive ability, socioeconomic outcomes and genomic ancestry in the United States.In regression models using 4 different codings of SIRE as a covariate, we found non-trivial relationships between genomic ancestry and outcomes. The relationship between genomic ancestry and cognitive ability was reduced but was still substantial when parental socioeconomic status was controlled for. Interpretation of this is unclear due to possible genetic confounding. Relationships also held when Hispanics and African Americans were analyzed alone.In this sample, the mean IQ by ancestry was approximately 100 for European, 78 for African, and 86 for Amerindian. The sample sizes for the remaining ancestries were too small to produce reliable estimates. The results are consistent with genetic models of cognitive and social inequality, but also with certain environmental models. More sophisticated studies are possible and necessary to resolve the question.