Fewer born with genetic predisposition for education
A genetic predisposition towards education seems to also be associated with having fewer children, suggests a new study.
The number of people with a genetic predisposition to take further education is falling, shows new research.
A new study published in the scientific journal PNAS shows that the same genetic variants that predispose people towards further education also predispose them to have fewer children.
“The cumulative effect over time means this is going to have a dramatic effect on the genetic predisposition to educational attainment, and unless something comes along to counteract that, it could have a profound effect on educational attainment in our society,” says lead-author Kari Stefansson, head of the genetic company deCODE, in The Guardian.
But equal access to education and other beneficial environmental impacts could counteract the genetic effect, he says.
Gene carriers have fewer children
In the new study, scientists have mapped the genome of over 100,000 people born between 1910 and 1990 in Iceland. They compared the participants’ genetic profiles with their education level and the number of children they had.
The analysis showed that the occurrence of gene variants associated with a high level of education had slightly declined.
In the same period, the participants that carried this gene were having fewer children.
Education-gene is in decline
Declining fertility in this group was not due to people struggling to balance further education or their career with having children, say the scientists. They also saw that the gene carriers who did not take further education also had fewer children.
It indicates that these genetic variants also predispose carriers to have fewer children, meaning that the genetic variant will continue to decline if the gene-carriers continue to have fewer children.
“If you are genetically predisposed to have a lot of education, you are also predisposed to have fewer children,” says Stefansson to The Guardian.
Fewer genes do not mean we are becoming more stupid
Even though the education-gene may be declining in the population, this does not mean that we are all becoming increasingly stupid or less educated.
Social and environmental factors also play an important role in how educated people are.
It is assumed that genetic factors account for between 20 and 40 per cent of variation in education level. The rest is due to other factors such as upbringing and access to education.
Education level is also generally on the rise throughout the world, says Mads Meier Jæger, a professor in the Department of Sociology at the University of Copenhagen, Denmark.
“Education levels have been dramatically increasing in general—regardless of the Icelandic discovery,” says Jæger.
“If at the same time there is a fall in the genetic group that is associated with education level, then we can interpret that as environmental effects winning out over the genetic effect,” he says.
Genetics is just a recipe
Genes undoubtedly play a role in whether we choose to take a further education, but the relationship between genetic and environmental factors is complex, says Jæger.
For example, research shows that our environment can play a role in which genes are expressed. This is known as epigenetics.
“We can compare it to baking a cake. Genes are the recipe and our environment provides the ingredients. The final result depends on the ingredients,” he says.
“Gene expression is very complicated and there’s still a lot that we don’t understand—such as how [genetic] inheritance and environment interact,” he says.
New study accounts for gene-interaction
Jonas Mengel-From an associate professor in molecular epidemiology at the University of Southern Denmark. He has read the new study and describes it as interesting.
“The scientists have evaluated the effect of genetic variants by assigning a polygenic score to 100,000 people,” says Mengel-From.
A polygeneic score represents the total contribution of many different genetic variants. In this case, a high score indicates more genetic variants that predispose the participants to furthering their education.
Genetic effect is not especially big
Mengel-From agrees that the new study does not automatically mean that we are becoming more stupid.
“We should be careful not to conclude from this study that people don’t take further education because they don’t have the genetic variant for it. The genetic effect is not especially high,” he says.
According to the study, the genetic variants can explain only 3.74 per cent of the variance in participants’ education level.
“Methodologically the study is interesting, but it doesn’t advance my understanding a whole lot. It’s new knowledge that there’s a genetic correlation between education level and fertility, but it’s not particularly surprising,” says Mengel-From.
More studies are needed before we can say with any certainty that there is a general decline in the occurrence of genetic variants that predispose us to a high level of education, he says. “I think that it’s too early to conclude that the education-gene has changed over time based on a single study—even though it is a large study.”
Scientists have long known that certain genetic variants can predispose us to embark on further education. Some of the genetic variants associated with higher IQ, and cognitive and personality traits, such as motivation, and conscience, also determine how likely we are to further our education.
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Read the Danish version of this article on Videnskab.dk
Translated by: Catherine Jex
