Researchers Identify 1,271 Genetic Variants Linked to Educational Attainment

A multinational team led by researchers at Vrije Universiteit Amsterdam and the Univesities of Queensland and Southern California, Los Angeles, has conducted a large-scale genetic association analysis of educational attainment in a sample of approximately 1.1 million individuals and identified 1,271 genome-wide-significant genetic variants. The findings, published in the journal Nature Genetics, shed new light on the role genetics play in influencing complex human behaviors.

Although primarily influenced by environmental and social factors, years of schooling are also influenced by genes associated with cognitive function such as memory and personality traits. Image credit: Sci-News.com.

“It moves us in a clearer direction in understanding the genetic architecture of complex behavior traits like educational attainment,” said co-author Robbee Wedow, a graduate student at the University of Colorado Boulder.

For the study, Wedow and colleagues analyzed a combined 71 datasets comprising over 1.1 million participants with European ancestry from 15 different countries and who were least 30 years old.

The data were from the UK Biobank Resource, the personal genomics company 23andMe, and the combined results of smaller genetic studies.

One of the previous studies had found that 74 gene variants, including many involved in brain development, were moderately predictive of educational attainment.

By using a far larger sample size for the current study, the team was able to identify 1,271 associated gene variants, including those involved with neuron-to-neuron communication and neurotransmitter secretion.

“It would be completely misleading to characterize our results as identifying genes for education,” said co-lead author Dr. Daniel Benjamin, from the University of Southern California.

Combined, the 1,271 variants explain about 4% of the variation in educational attainment across individuals.

“Even variants with the largest effects predict, on average, only about three more weeks of schooling in those who have those variants compared to those who don’t,” Dr. Benjamin said.

“Yet, when we analyze the combined effects of many genetic variants, taken together they can predict the length of a person’s formal education as well as demographic factors.”

When the scientists included the effects of all of the variants they measured across the genome to develop a new polygenic score, they found that the score was predictive of 11-13% of variation in years of completed schooling.

That makes the score’s predictive power for educational attainment equivalent to that of demographic factors, like household income or maternal education.

“That is a large effect for a polygenic score, especially for a behavioral outcome,” Wedow said.

“While useful for research, the polygenic score is by no means deterministic,” he added.

“The very small effects of individual genetic variants confirm what we’ve seen in our earlier work, and it’s an important finding in itself,” Dr. Benjamin said.

“It would be completely misleading to characterize our results as identifying ‘genes for education’.”

“Yet, the polygenic score is useful for research because it combines the effects of a very large number of genetic variants.”

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James J. Lee et al. Gene discovery and polygenic prediction from a genome-wide association study of educational attainment in 1.1 million individuals. Nature Genetics, published online July 23, 2018; doi: 10.1038/s41588-018-0147-3