Should We Use Genetic Technology to Boost Human Intelligence?

By Julien Delhez | 5 January 2019

(Photo by Amanda Dalbjörn on Unsplash)

Chinese researcher He Jiankui is now world-famous for having announced the creation of genetically-modified twins that would be resistant to HIV. He said that he edited the genomes of these twins with CRISPR/Cas9, a technology that makes it possible to target specific genes within a living organism. Everywhere, scientists and non-scientists alike reacted with astonishment. Most comments were negative, but not all were critical of gene editing per se.

Julian Savulescu, the Uehiro Professor of Practical Ethics at Oxford who favors gene editing and embryo selection, released a press statement denouncing Jiankui’s decision to perform the experiment on healthy babies instead of on embryos that had fatal genetic diseases and would be certain to die in the absence of the intervention. He also pointed out that gene editing is still experimental and “capable of causing genetic problems early and later in life, including the development of cancer.”

By contrast, Marcy Darnovsky, the Executive Director of the Center for Genetics and Society and a long standing critic of genetic editing, wrote: “In a time of resurgent racism and socio-economic disparity, the last thing we need is for some people and groups to consider themselves biologically superior to others.”

Irrespective of He’s ethics (or lack of them), there is still much resistance to the idea of genetic enhancement, although the degree of resistance often depends on what traits we’re talking about enhancing.

Take intelligence. General cognitive ability, or Spearman’s g, is a trait that has a profound effect on social outcomes, both at the individual level and at the collective level. A technology that enhanced this trait would have consequences that we can barely envisage. To date, no such technology is available. But we had better start discussing cognitive enhancement soon if we’re to be ready to act responsibly when the technology comes on stream.

To be clear, the debate we need to have is whether cognitive enhancement is desirable once technological mastery has been achieved, and once the chosen technique is completely safe. No one is seriously proposing experimenting with embryos now. Since intelligence is a complex trait influenced by many genes, using CRISPR/CAS9 to try and enhance it would be a more challenging task than the technology was originally designed for and could increase the chances of off-target mutations. In addition, there would be unknown risks associated with editing dozens or even hundreds of genes, many of which have effects we’re unaware of. Testing embryos and implanting those likely to have high IQs would be safer, given that the embryos in question would not be genetically edited. However, even that isn’t yet possible since we still don’t know enough about the many genes linked to IQ to accurately predict which embryos are likely to turn into highly intelligent adults. But what should we do once cognitive enhancement has become both possible and safe?

The Weight of History

Before delving into the topic, it is worth addressing the concerns of Marcy Darnovsky who has warned about the “emergence of a market-based eugenics,” among other things. The word “eugenics,” which is freighted with a lot of historical baggage, is often thrown at contemporary advocates of genetic enhancement as a way of discrediting their views. But what do these enthusiasts have in common with early eugenicists?

The eugenics movement of the late nineteenth and early twentieth centuries comprised a wide variety of personalities, all of whom shared two central convictions: First, that behavioral tendencies are at least partly inherited; and second, that society will benefit if we increase the frequency of traits like good health and intelligence in the general population. Aside from these two core beliefs, the movement was very heterogeneous. It included conservatives and socialists, feminists and opponents of birth control, and even Lamarckians as well as Darwinians (see A. Buchanan et al., From Chance to Choice, Cambridge University Press, 2011, p.32-37).

Eugenicists also differed on the means to achieve their aims. Some proposed compulsory sterilization laws and bear some responsibility for the introduction of those laws in Europe and the U.S. and the cruel sterilization of tens of thousands. However, the signatories of the 1939 manifesto “Social Biology and Population Improvement“―which aimed to answer the question: “How could the world’s population be improved most effectively genetically?”―only endorsed voluntary sterilization, along with contraception and abortion. The signatories hoped for “the removal of racial prejudices and of the unscientific doctrine that good or bad genes are the monopoly of particular peoples or of persons with features of a given kind.” This should warn us against any monolithic view of twentieth-century eugenics.

Instead of using the label “eugenics” to discredit advocates of genetic enhancement, it would be more productive to ask what precisely we deem unacceptable and why. We should distinguish between measures that were adopted in the name of eugenics, such as compulsory sterilization, and the goal itself, which can be achieved by other means. Today, our understanding of human heredity, and how to influence it, is far more advanced than it was in the early twentieth century. With further research into the relevant technologies, as well as a careful debate on the ethics of genetic enhancement, we might be able to influence human genetic development in a way which is both humane and socially beneficial.

Misconceptions About Intelligence

There are many misconceptions about intelligence, both among the general public and educated people. He Jiankui himself was quoted in the MIT Technology Review saying he was perfectly happy to use CRISPR to eliminate diseases “but not for enhancement or improving IQ, which is not beneficial to society” (my emphasis). On the face of it, that’s an odd claim to make. Intelligence is, to quote a largely accepted definition, “a very general mental capability that, among other things, involves the ability to reason, plan, solve problems, think abstractly, comprehend complex ideas, learn quickly and learn from experience.” Far from being a mere academic skill―as Nassim Taleb claimed recently―IQ is positively correlated with many important traits and life outcomes, including altruism, creativity, job performance, longevity, sense of humour, socioeconomic success, and even semen quality (see James Thompson’s rebuttal of Taleb); it is also negatively correlated with many outcomes that most people would regard as undesirable, including accident proneness, crime and delinquency, impulsivity, infant mortality, political extremism, and prejudice towards racial minorities. (For more correlates, see A. Jensen, The g factor, Praeger, 1998, p.300 and E. Dutton & M. A. Woodley of Menie, At Our Wits’ End, Imprint Academia, 2018, p.11).

Not all variations in these life outcomes can be explained by environmental variables such as socio-economic status (SES). IQ is a better predictor of personal SES than parental SES, although both are important, and IQ is both an influence on and is influenced by SES (see S. Ritchie, Intelligence: All that matters, John Murray Learning, p.43-47). In addition, for those born in families that are already below the poverty line, IQ significantly predicts the likelihood of escaping poverty. More generally, IQ in childhood is a good predictor of upward and downward social mobility.

These correlates mean that if there was some way to guarantee that a child was born with an above-average IQ, that child’s life would be improved, both professionally and personally (myopia is a rare exception), in the opinion of most parents. Intelligence is by no means all that matters, but it is clearly a valuable asset. Perhaps most significantly for parents, higher IQ is associated with greater happiness, even after controlling for other important variables such as SES and health. Parents who understand this and want their child to be happy, as most parents do, would not hesitate for long if asked whether they would prefer their child to have a high or low IQ, whatever their child’s goals might be.

A high IQ is advantageous not only for children themselves, but also for their parents, since it constitutes a protective barrier against juvenile delinquency and school failure. Of course, smart children are more likely to ask complex questions frequently and this may be exhausting at times. They are also much harder to fool when you want to (but nobody said you should).

IQ and the Common Good

A high IQ benefits not only those who have it, but often those who live around them. Apart from the obvious advantages of altruism, society clearly benefits from the presence of individuals who are productive, law-abiding, supportive of individual liberties, and resistant to racism and other forms of extremism (to give just a few examples). Unsurprisingly, nations with high average IQs are far more prosperous than those with low average IQs, partly because groups with higher intelligence are more patient, more cooperative, and better informed, which has a decisive impact on how well national industries fare.

One of the objections leveled against gene editing and embryo selection is that they would only be available to wealthy families and that would exacerbate intellectual and socio-economic differences and lead to what Darnovky calls “a society of genetic haves and have-nots.” This is a legitimate concern. However, it’s not a knock-down argument against genetic enhancement. Darnovky may not like it, but we already live in a society where some people have genetic advantages. Therefore, cognitive enhancement could be used to reduce cognitive inequality, depending on how it is implemented.

The genetic process might be quite expensive to begin with, thereby restricting its use to the very rich, but technologies tend to become much cheaper over time. In 2006, sequencing an entire human genome cost around $14 million dollars. In 2014, full genomes could be sequenced for $1000, and in November 2018 Veritas Genetics offered the first opportunity to have full genomes sequenced for $200. In the future, companies offering cognitive enhancement would likely reduce the price of their services as well, thereby making it affordable to the broad mass of people.

Even if cognitive enhancement was initially a service that only the wealthy could afford, many others would benefit from such enhancement, not just the children of the rich. With more high IQ individuals, there would be more breakthroughs in medical research, and also more creative accomplishments, whether scientific, artistic, or literary. According to a 2012 study by Ruut Veenhoven & Yowon Choi, an individual’s happiness level is better predicted by her nation’s average IQ than by her own IQ. Obviously, in the long term, most of us would reject a society of genetic haves and have-nots. But increasing the IQ of certain individuals would only be a first step towards a world of relatively uniform and high intelligence, in which everyone would have a fair chance of being socially, economically, and educationally successful.

For some traits, it is less easy to decide whether genetic editing is desirable. Extraversion, for instance, has both benefits and drawbacks. But no such dilemma exists for intelligence. Both in terms of individual wellbeing and the common good, high intelligence is clearly a beneficial trait. Cognitive enhancement should make it possible to increase it without infringing individual rights or invoking irrational prejudices.

Several polls have found that Americans are in favor of using gene editing to reduce the risk of serious diseases, but not for improving IQ. However, the public has not always been given clear information about intelligence by the media in the last 50 years, so may be basing this preference on false notions. With fewer misconceptions about intelligence, perhaps less people would regard cognitive enhancement as dangerous or undesirable. By increasing their children’s intellectual potential, parents would increase both their likelihood of being happy and their ability to make the world a better place.

If We Do Nothing

Perhaps the reason so many people oppose gene manipulation to boost intelligence is because they’re reluctant to change a child’s nature, particularly when it’s not necessary to save the child’s life or ensure she’s healthy.

In a 2017 poll, the pollsters drew a clear line between two purposes of gene manipulation: “to treat medical conditions or restore health” and “to enhance or improve human abilities.” In real life, though, it is not always easy to tell what constitutes a disability and what doesn’t. An IQ of 65 does not qualify as a disease. Yet it is associated with significant shortcomings in many aspects of life, including difficulty in finding fulfilling employment. If it was possible to raise the prospective IQ of an embryo from 65 to 90 or 95, doing so would likely prevent much suffering.

What about children who are already destined to have above-average IQs? Is there any benefit in manipulating their genes to make them even more intelligent? Yes. In recent years, there have been increasing concerns about a decline in average intelligence in Western countries. The warnings have come from researchers such as Richard Lynn, Michael A. Woodley of Menie, Gerhard Meisenberg, and also James Flynn, who declared at the 2017 ISIR conference: “I have no doubt that there has been some deterioration of genetic quality for intelligence since late Victorian times.”

In 2017, an Icelandic study found direct evidence for a decline in genotypic intelligence: the authors noticed a decline in the frequency of genetic variants associated with educational attainment. They pointed out that “if this trend persists over many centuries, the impact could be profound” (p.E730). This tendency is not often debated in public, but it could indeed endanger Western societies’ ability to maintain economic prosperity, peace, liberty, and democracy, all of which require people who are able to delay gratification, resist simplistic, one-size-fits-all ideologies, and deal responsibly with the freedoms they enjoy.

In addition, we now live in a world where technology is omnipresent, and where numeracy, computer skills, scientific literacy, and economic competence are of ever-increasing importance. Most of the jobs that disappeared in the twentieth century were unskilled jobs, and most of those that will appear in the twenty-first and twenty-second centuries will likely require highly specialized abilities. Without a sufficient level of average intelligence, we may be unable to find enough people to do these new jobs.

But that is not my main concern. From 1850–2000, our world saw immense technological breakthroughs in a wide variety of areas. These profoundly changed society and yielded many benefits, but also gave rise to many new challenges. In his recent book On the Future (2018), Royal Astronomer Martin Rees addresses some of them, including nuclear threats (p.17-20), climate change (p.37-44), the search for alternative energy sources (p.44-57), GM crops (p.66), the increasing resistance of pathogens to antibiotics (p.72), and the promises and risks of artificial intelligence (p.83-90). Rees does not address the decline in human intelligence, but he notices one common cause of humanity’s problems:

there is too little planning, too little horizon scanning, too little awareness of long-term risks. (p.226-227)

This is precisely why intelligence matters. Today’s world is full of possibilities and full of dangers. We humans of the twenty-first century have powers that go far beyond the Greeks or the Romans’ wildest dreams, including the power to end civilization itself. Yet our intelligence is no more developed than it was in 1850, even though numeracy and literacy have improved. Can we preserve ourselves from all the major risks we fear? We may have become, to quote Russian Deputy Minister Dmitri Rozogine, “monkeys playing with hand grenades.”

Gene editing and embryo selection still elicit a good deal of resistance. But in the next decades, humanity will need highly-intelligent visionaries who can see the long-term consequences of political decisions, assess benefits and risks with accuracy, and find solutions to the problems of our increasingly complex world. If we wish to overcome our current difficulties and offer a bright and safe future to our children, cognitive enhancement will surely help.

I do not pretend that all the opponents of these ideas are motivated by fear or ignorance. There may be some valid arguments that I am not aware of, and I would be happy to engage with them. But these have to be serious arguments. Name-calling, ad hominem attacks and attempts to get research scientists defunded or fired can only delay debate on this vital issue. Future discussions should be based on the ethics and the difficulties of future genetic technologies, assessing the benefits and risks, and also an assessment of the risks of not acting. We should acknowledge that even with safe and advanced technologies, it is impossible to predict the impact of our choices with absolute precision. On the other hand, it is not hard to predict what will happen if humanity’s intelligence does not grow to solve present and future problems. We need to start talking about which risk is greater.

Reprinted with permission from the author.

Julien Delhez is a Ph.D. student in the department of Egyptology/Coptology at the University of Göttingen. All views expressed here are his own.

Pioneering gene-editing | George Church & Chris Smith

Homo Sapiens 2.0: The Future of Human Genetic Engineering – Jamie Metzl (Atlantic Council)

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  1. Very interesting article. Thank you. Let me add a few comments though.
    It seems to me there is no lack or deficit of intelligence within the human race. We've managed to eradicate the worst epidemics that plagued History, most of mankind eats enough and drinks acceptable water, we explore Mars and the Solar system and we even know how to edit genes. Frankly where would the shortage of intelligence be ?
    However there are many things that could or should be profoundly improved. To name a few,
    Across the board (male and female) and life-long Education
    Critical thinking,
    good will,
    reason and the list could go on for quite a bit.
    These are the human dispositions that mankind lacks most and where we should be making great strides.
    So the question is: are we anywhere near being capable of gene editing that would somehow improve those traits ?
    I have never heard of any research work moving in that direction.
    Barring any significant progress in those, we should wisely stay clear of direct gene editing for the purpose of improving intelligence alone.
    Pascal Masi


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