Science: There Is No Such Thing As A ‘Smart Gene’

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One of our greatest social fears has long been that our genetics point to our immoveable, unstoppable destiny. Movies like Gattaca imagine a world where your place in society is decided entirely at birth by a blood test and babies are custom-designed. To this day, you can find people insisting that, whether good or bad, people are born to be whatever they are and that there’s nothing we can do. But as genetic research has improved we’ve found the exact opposite to be true. It turns out that genetics isn’t the biggest factor in determining who we are as people. And a recent scientific study delivers a hard blow to the idea that genetics are destiny, namely by disproving people are born smart or stupid.

Daniel Benjamin of USC spent the last five years engaging in a huge study of genetics, to determine how they impact educational attainment — pretty much the only remotely quantifiable metric in the messy world of defining what we call “intelligence.” Benjamin started out with 100,000 genetic samples, then tripled it. Eventually, he looked at over one million people of European descent and found over 1,271 genetic factors that appear to have some sort of potential impact on how long you go to school.

Case closed, right? Just design your baby to fit those factors!

Nope. In fact just the opposite. Benjamin’s list of factors and where people fall on them, called a “polygenic score,” is actually terrible at determining the educational attainment of an individual person, something he’s at pains to point out in a long FAQ written about the study:

These results show both that polygenic scores have some predictive power but also that polygenic scores do not determine or pin down individual outcomes: even when polygenic scores are based on GWAS [genome-wide association study] of many more people and therefore have even greater predictive power than ours, there will always be many people whose polygenic scores “predict” lower educational attainment who in fact attain relatively high amounts of education and vice-versa.

The exact contribution, in terms of an overall trend? Eleven percent. And Benjamin is convinced this is about as accurate as it’s going to get. What the study instead finds is that while you can determine an overall trend from the scores, genetics are just one factor in educational attainment. Household income, family circumstances, personal health, psychological factors, and a giant list of others also contribute and clearly have much more of an effect.

Benjamin also highlights that these factors are not objective. Speaking with The Atlantic, he points out you would have gotten a very different result using the same tools a century ago:

“If you did a study like ours 100 years ago, the strongest genetic predictor of education would be how many X chromosomes you had, because society was set up in a way that it was much harder for women to get educated than men,” says Benjamin. Likewise, many of the genes that are associated with education today are likely important “because of how today’s educational system is set up. It requires people to sit at desks for hours, and listen to instructions from a teacher. People who get restless, or are less obedient to authority, will fare less well in that environment.”

This pretty much scrubs out the idea that “genetics = destiny.” The reality is that for too long, we’ve used genetics as a form of social excuse. Some people are just dumb, so why do they need better schools, more teachers, libraries, and all the other things that help people rise and gain knowledge? What we’re increasingly seeing is that just the opposite is true, and that if we want to fix our social problems, we need to fix our societies.

(via The Atlantic