NYU (US) — Scientists have identified genetic markers that predict educational attainment based on data from more than 125,000.
However, the researchers are careful to note that they have not discovered “the gene for education” or that the findings somehow imply that a person’s educational attainment is determined at birth.
The team conducted what is called a genome-wide association study to explore the link between genetic variation and educational attainment—the number of years of schooling completed by an individual and whether he or she graduated college.
Because the sample included people from the United States, Australia, and 13 western European countries—where markers for schooling vary significantly—the research team adopted the International Standard Classification of Education scale, which is a commonly used method for establishing a uniform measure of educational attainment across cohorts.
Anticipating that very large samples would be required to credibly detect genetic associations, the researchers assembled a total sample size more than 10 times larger than any previous genetic study of any social-scientific outcome. Their findings appear in the journal Science.
Genetics and the social sciences
The team examined associations between educational attainment and genetic variants called single-nucleotide polymorphisms, or SNPs, which are tiny changes at a single location in a person’s genetic code.
The analysis showed that the genetic markers with the strongest effects on educational attainment could each only explain two one-hundredths of a percentage point (0.02 percent). To put that figure into perspective, it is known from earlier research that the SNP with the largest effect on human height accounts for about 0.40 percent of the variation.
Combining the two million examined SNPs, the researchers were able to explain about two percent of the variation in educational attainment across individuals, and anticipate that this figure will rise as larger samples become available.
“We hope that our findings will eventually be useful for understanding biological processes underlying learning, memory, reading disabilities, and cognitive decline in the elderly,” says co-author Daniel Benjamin, a behavioral economist at Cornell University who is a co-director of Social Science Genetic Association Consortium (SSGAC), the research team that conducted by study.
“Another contribution of our study is that it will strengthen the methodological foundations of social-science genetics,” says David Cesarini, a New York University assistant professor at the Center for Experimental Social Science and the Center for Neuroeconomics, who also co-directs the SSGAC.
“We used 125,000 individuals to conduct this study. Previous studies used far smaller samples, sometimes as small as 100 individuals and rarely more than 10,000. These small samples make sense under the assumption that individual genes have large effects. However, if genes have small effects, as our study shows, then sample sizes need to be very large to produce robust findings that will reliably replicate in other samples.”
“For most outcomes that we study as social scientists, genetic influences are likely to operate through environmental channels that are modifiable,” explains NYU sociologist Dalton Conley, one of the study’s co-authors who also serves on the Advisory Board of the SSGAC.
“We have now taken a small but important first step toward identifying the specific genetic variants that predict educational attainment. Armed with this knowledge, we can now begin to examine how other factors—including public policy, parental roles, and economic status—dampen or amplify genetic effects and ultimately devise better remedies to bolster educational outcomes.”
The National Institutes of Health, National Science Foundation, and the Söderbergh Foundation supported the research.