We Won't Engineer Superhumans Any Time Soon...,

aeon |  A paper published in Nature Genetics in 2017 reported that, after analysing tens of thousands of genomes, scientists had tied 52 genes to human intelligence, though no single variant contributed more than a tiny fraction of a single percentage point to intelligence. As the senior author of the study Danielle Posthuma, a statistical geneticist at the Vrije Universiteit (VU) Amsterdam and VU University Medical Center Amsterdam, told The New York Times, ‘there’s a long way to go’ before scientists can actually predict intelligence using genetics. Even so, it is easy to imagine social impacts that are unsettling: students stapling their genome sequencing results to their college applications; potential employers mining genetic data for candidates; in-vitro fertilisation clinics promising IQ boosts using powerful new tools such as the genome-editing system CRISPR-Cas9.

Some people are already signing on for this new world. Philosophers such as John Harris of the University of Manchester and Julian Savulescu of the University of Oxford have argued that we will have a duty to manipulate the genetic code of our future children, a concept Savulescu termed ‘procreative beneficence’. The field has extended the term ‘parental neglect’ to ‘genetic neglect’, suggesting that if we don’t use genetic engineering or cognitive enhancement to improve our children when we can, it’s a form of abuse. Others, like David Correia, who teaches American Studies at the University of New Mexico, envisions dystopian outcomes, where the wealthy use genetic engineering to translate power from the social sphere into the enduring code of the genome itself.

Such concerns are longstanding; the public has been on guard about altering the genetics of intelligence at least since scientists invented recombinant DNA. As long ago as the 1970s, David Baltimore, who won a Nobel Prize, questioned whether his pioneering work might show that ‘the differences between people are genetic differences, not environmental differences’.

I say, dream on. As it turns out, genes contribute to intelligence, but only broadly, and with subtle effect. Genes interact in complex relationships to create neural systems that might be impossible to reverse-engineer. In fact, computational scientists who want to understand how genes interact to create optimal networks have come up against the kind of hard limits suggested by the so-called travelling salesperson problem. In the words of the theoretical biologist Stuart Kauffman in The Origins of Order (1993): ‘The task is to begin at one of N cities, travel in turn to each city, and return to the initial city by the shortest total route. This problem, so remarkably simple to state, is extremely difficult.’ Evolution locks in, early on, some models of what works, and hammers out refining solutions over millennia, but the best computer junkies can do to draw up an optimal biological network, given some input, is to use heuristics, which are shorthand solutions. The complexity rises to a new level, especially since proteins and cells interact at higher dimensions. Importantly, genetics research is not about to diagnose, treat or eradicate mental disorders, or be used to explain the complex interactions that give rise to intelligence. We won’t engineer superhumans any time soon.