In what is the largest-ever genome wide association study for social science, researchers found more than 70 genetic variants associated with educational attainment – the number of years individuals spent in school or university.
Many of the variants found were also in genes or gene regions associated with cognitive performance, intracranial size, bipolar disorder and a decreased risk for either Alzheimer’s disease or neuroticism.
“It is not surprising that genes seem to matter for educational attainment in part because of their effects on brain development,” said the study authors, who are part of the Social Science Genetic Association Consortium. The new findings appeared in the latest issue of Nature.
The three primary authors of the study – Daniel Benjamin, at the University of Southern California, David Cesarini, at New York University and Philipp Koellinger, at Erasmus University in Rotterdam – said certain cognitive abilities and personality traits that matter most for school performance are likely also to reflect how the brain is organized.
“It is intriguing that, even though educational attainment is primarily influenced by environmental factors, our study of educational attainment generates a biological picture of brain development that is clearer than those generated by previous GWAS that focused directly on brain structures,” the authors said.
The researchers identified 74 genetic variants associated with educational attainment, and noted that these variants were in genes or gene regions associated with the development of neural tissue, particularly during prenatal development. Although the genetic associations identified only explain a small portion of the variation for educational attainment, the researchers said the results highlight candidate genes and pathways that should be the focus of future study.
This is the second time the consortium, which includes scientists from a dozen institutions around the world, has looked specifically at educational attainment.
The last study, published in 2013, found just three variants, but that research was only a third of the size of this latest study.
This latest research includes data from more than 300,000 individuals including data from more than 76,000 23andMe customers who consented to research. 23andMe’s contribution was by far the largest of all the 64 cohorts included in the study, which included people from 15 different countries. 23andMe’s principal scientist David Hinds, director of research Joyce Tung, and statistical geneticist Nick Furlotte also contributed to the work.
The researchers noted that it is the size of this study that allowed them to find specific genetic variants that may not have a big effect but are clearly associated with educational attainment.
For the members of the consortium the study reinforced the value of using genome-wide association studies for social science research. At the same time, they took pains to emphasize that educational attainment is much more strongly influenced by social and environmental factors such as the school system where someone is raised.