A Polygenic Score for Higher Educational Attainment is Associated with Larger Brains.

Journal Article (Journal Article)

People who score higher on intelligence tests tend to have larger brains. Twin studies suggest the same genetic factors influence both brain size and intelligence. This has led to the hypothesis that genetics influence intelligence partly by contributing to the development of larger brains. We tested this hypothesis using four large imaging genetics studies (combined N = 7965) with polygenic scores derived from a genome-wide association study (GWAS) of educational attainment, a correlate of intelligence. We conducted meta-analysis to test associations among participants' genetics, total brain volume (i.e., brain size), and cognitive test performance. Consistent with previous findings, participants with higher polygenic scores achieved higher scores on cognitive tests, as did participants with larger brains. Participants with higher polygenic scores also had larger brains. We found some evidence that brain size partly mediated associations between participants' education polygenic scores and their cognitive test performance. Effect sizes were larger in the population-based samples than in the convenience-based samples. Recruitment and retention of population-representative samples should be a priority for neuroscience research. Findings suggest promise for studies integrating GWAS discoveries with brain imaging to understand neurobiology linking genetics with cognitive performance.

Full Text

Duke Authors

Cited Authors

  • Elliott, ML; Belsky, DW; Anderson, K; Corcoran, DL; Ge, T; Knodt, A; Prinz, JA; Sugden, K; Williams, B; Ireland, D; Poulton, R; Caspi, A; Holmes, A; Moffitt, T; Hariri, AR

Published Date

  • July 2019

Published In

Volume / Issue

  • 29 / 8

Start / End Page

  • 3496 - 3504

PubMed ID

  • 30215680

Pubmed Central ID

  • PMC6645179

Electronic International Standard Serial Number (EISSN)

  • 1460-2199

International Standard Serial Number (ISSN)

  • 1047-3211

Digital Object Identifier (DOI)

  • 10.1093/cercor/bhy219


  • eng