A study released today has found that an individual’s genetic makeup can have a direct effect on the level of education achieved by that individual, the first time that researchers have found such a relationship. And while the impact is found to be relatively small compared to other external factors, the researchers say it's still significant enough to consider.

This new study, published in AERA Open, a journal of the American Educational Research Association, builds on an existing body of work on how genetics can contribute to what level of education a person receives. A 2013 study from New York University identified the genetic markers that contribute to a person’s level of education, using a pool of 125,000 people from Western Europe, Australia and the U.S.

From those markers, a score referred to as a “polygenic score” is created, estimating just how many years of education a person will complete. But researchers were still unclear on the effects of other factors, like an individual’s upbringing, neighborhood and socioeconomic status.

Now, researchers in this new study say that they were able to find a direct cause-and-effect relationship between genetics and educational attainment. And while social factors, like having a parent who has earned a college degree, may have a larger effect on a person’s decision to pursue a higher education, genetics can still create a predisposition toward the level of education reached.

Five researchers from colleges throughout the country looked at more than 1,500 siblings in a database known as the National Longitudinal Study of Adolescent to Adult Health. After identifying siblings within the group -- based on the assumption that they would have the same socioeconomic status, parents and neighborhoods -- and comparing their polygenic scores, they found that a sibling with a higher score is more likely to complete more schooling than a sibling with a lower score.

This does not mean that the sibling with the lower score will automatically not reach a higher level of education than the higher-scoring sibling, said Benjamin Domingue, an assistant professor at the Graduate School of Education at Stanford University and a co-author of the paper. He noted that the higher-achieving sibling on average only completed a little less than a third of year of additional schooling compared to the lower achieving sibling.

“It can’t be due to being in different environments because they have the same parents, they go to the same schools, they have more or less the same upbringing,” said Domingue. “The sibling divide suggests that the genetic relationship is indeed causal.”

Domingue said that while the data are new and have to be explored further to effectively apply them in the real world, his findings have implications for the future use of genetics in education. He said policies may be created to make sure that those who may not necessarily be genetically inclined to pursue a higher level of education are still encouraged to do so, and that other factors do still come into play with an individual’s decision to complete more years of college.

The paper used a younger group of respondents than past studies that have examined the impact of genetics on education have used. All respondents were in their late 20s or early 30s.

The study also found that with black siblings, the genetic effect was smaller but still significant enough to have an impact. This is the first time that a paper has looked at the genetic impact on level of education attained for the black population.

Domingue said research he and others are working on for a future paper indicates that other factors aligned with success are also associated with pursuing a high level of education -- although it is possible for an individual to achieve success without additional degrees.

“People who are more disposed to get additional years of schooling also have other successes later in life …. This is associated with kind of important things downstream, but more years of education is not the only path to health and stability,” he said.