Can DNA Tests Predict Intelligence or IQ?

January 14. 2019. 6 mins read

With the emergence of big data and machine learning, we’re now able to do all kinds of things that we couldn’t do before. While genetic testing started out as something you could use to find out if your dad is actually the milkman, it has now progressed into other areas. We recently wrote about how polygenic risk scores are being used to predict everything from a person’s height to their susceptibility towards mental illnesses. In a piece we wrote a while ago on genetic modification at the germline, we discussed a topic that is as equally fascinating as it is controversial – can DNA tests predict intelligence or IQ?

Can DNA Tests Predict Intelligence?

If you’re not familiar with twin studies, you should read up on this fascinating topic. Since identical twins share nearly 100% of their genes, differences between two identical twins can be largely attributed to environmental differences. If a pair of twins were raised in separate environments, the differences they exhibit should be attributed to nurture, not nature. This unique method allows researchers to identify how DNA affects traits.

One man who leads a long-term twin study consisting of 13,000 twins is an American by the name of Robert Plomin, a deputy director of the MRC Social, Genetic and Developmental Psychiatry Center at King’s College London. He answered the question about whether or not DNA tests can predict intelligence in an article by the Scientific American titled “Is Intelligence Hereditary,” in which he makes the following statement:

Scientists have investigated this question for more than a century, and the answer is clear: the differences between people on intelligence tests are substantially the result of genetic differences.

One example of mental capabilities tied to genetics is found in idiot savants or people afflicted with Fragile X syndrome, a topic we discussed in our recent article on When Will There be a Cure for Autism? The mental capabilities of these unique individuals can be attributed to their DNA, not what their parents or teachers taught them.

One reason the “genetic testing for intelligence” topic makes some people uncomfortable is that many don’t want to know if they might have drawn the short straw when it comes to the genetic lottery of intelligence. But, let’s be realistic here. Is there any single person out there who would take a genetic test for intelligence and disagree if it incorrectly reported that they were brilliant? Conversely, would they quietly agree with the outcome of the test if it said they were not so bright? You can probably guess the answer to those questions. If that’s the case, then why not just sell a DNA test that tells everyone they’re a genius? That would probably go over well in America, but not in China.

Precision Education

It seems pointless to sell a genetic intelligence test product to the public if the product actually works because then half the people would probably disagree with the results since nobody likes being told that they have below-average intelligence. That’s how 23andMe probably feels, according to an article by MIT Technology review last spring, which said they sense that “the information would be poorly received.” The same article went on to say that more than 500 genes have been tied to IQ test results from gene studies involving more than 200,000 test takers. And there’s a forthcoming report which will soon establish links to 1,000 genes. Again, Robert Plomin comes up in the below excerpt taken from the same article:
The discoveries mean we can now read the DNA of a young child and get a notion of how intelligent he or she will be, says Plomin, … [who] outlined the DNA IQ test scenario in January in a paper titled “The New Genetics of Intelligence,” making a case that parents will use direct-to-consumer tests to predict kids’ mental abilities and make schooling choices, a concept he calls precision education.
Yikes. If that makes you uncomfortable and you think it should be banned, guess who won’t be banning that? Cultures like the Chinese, who obsess more than anyone else out there about making sure their children are equipped to succeed in the education system no matter what it takes. They’re going to use information like this to run circles around those people who opt not to utilize it. Yes, that makes some people uncomfortable. Get over it, because that’s where we’re heading now. The responsible thing to do is decide how we’re going to manage this while keeping in mind how everyone else around the globe will be utilizing this information.

DNA Tests to Predict Intelligence Today

Right now, there are at least a few test providers who offer DNA tests that are associated with intelligence. The key word here is “associated.”


One Belgian company called GenePlaza is trying to emulate the Helix business model by having you upload your DNA information (or take their own DNA test) after which you can access apps like this one:

So, for $6.89 they will tell you how you compare to the other people that shelled out $6.89 for the test. (The fact that they need to tell the reader that the sample shown on their website is actually a sample implies that if you take the test, you may be a big fish swimming in a little pond.) Intelligent people would just pass after reading the disclaimer that says that “for most people, these Single Nucleotide Polymorphisms (SNPs) do not influence their intelligence in any particular direction” and for those that it does, they have a “minuscule” effect on IQ.

DNA Land

Then there’s a test from a U.S. non-profit called DNA Land which also provides you with a bell curve that’s based on the same 2017 study that the previous company uses. There’s an article published in the Atlantic titled “Genetic Intelligence Tests Are Next to Worthless” which described how science writer Carl Zimmer took the test and landed just left of center.

A DNA Land example of a DNA intelligence test
Source: The Atlantic

He then contacted Yaniv Erlich, the scientist who wrote the intelligence program, who said he also fell just left of center, and that “Everything is cool. Many smart people end up there” and admitted he wrote the test just to “make people cautious about the connection between genes and intelligence.” They both had a good chuckle about how clever an idea that was, and went on their merry ways. Again, not the sort of test that anyone intelligent ought to consider taking.

To Fix or Not to Fix

Going back to the article we wrote last year about genetic editing at the germline, it seems that most people oppose the idea of choosing embryos that are highly intelligent. According to a survey by MIT Technology Review, half of the people think genetic modification of babies is just fine for serious diseases while 83% think that making the baby more intelligent is going too far.

Source: MIT Tech Review

So what about someone who has an extremely low IQ, like a person with Fragile X syndrome? Where do we draw the line exactly?

Someone once speculated that when the ability to advance human intelligence arrives, there will be two camps. Camp One will adopt the technology and Camp Two won’t. Then, because the intelligence increases will lead to more intelligence increases and intelligence will grow so exponentially, Camp One will grow so monstrously intelligent that they’ll throw all the Camp Two people into large zoos and just view them as a form of amusement, kind of like how we keep pets today.

The point is, if even a small minority choose to advance human intelligence using technology, there are going to be some societal problems that will arise as a result. We already have DNA testing for dating, so it’s not a far stretch to think that some people would demand a similar level of intelligence as their own from the person they decide to procreate with. (It’s funny how everyone who drives a car today complains that everyone else on the road is a “stupid moron,” but as soon as you start to suggest that just maybe “stupid morons” shouldn’t be allowed to procreate, people start vehemently objecting to the idea.)


“Intelligence is highly heritable and predicts important educational, occupational and health outcomes better than any other trait.” That statement was taken from the paper we mentioned earlier co-written by Robert Plomin which goes on to say that up until 2017, we could only explain 1% of intelligence using genetic testing. Now, all that has changed, and we may be on the cusp of being able to predict someone’s success in life before they are even born. There are certainly scientists out there that disagree with Dr. Plomin, but the use of polygenic scores to determine traits isn’t going anywhere, and it’s now up to mankind to decide how to best manage this new form of genetic fortune-telling.

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  1. “GenePlaza is trying to emulate the Helix business model by …” just to point out that Helix is actually the new kid on the block here. GenePlaza has been running since early 2017. And they are anyway just both copies of the original open-source calculations available at impute-me, just selling them for a fee in a nice interface, instead of free. I think I even saw a tweet exchange that the GenePlaza algorithms *is* the impute-me algorithms re-packaged. Only fun twist is that the makers of impute-me decided that current intelligence-prediction was not up to par and packed it off in a non-listed module instead. So the commercial operators are selling the stuff that the free ones feel is not good enough. Fun comment on the world.

    1. Thank you for the added information. Very insightful.

      We’re seeing Helix listed in Crunchbase with a “founded” data of 2015. Helix is working with $300 million and backing from Illumina, Mayo Clinic, kleiner Perkins, those types. It will be very tough to go up against them but that’s not all that bad as competitors could just look to exit through assimilation.

      What’s most interesting about this aspect of the business is the controversy surrounding it which means some companies will opt not to go there which leaves the door open for smaller entrants to capture market share quickly.