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Chinese scientist He Jiankui had sidestepped his own field's codes of practice to test gene-editing on two embryos that were then implanted, and carried to term, and are now living children
Reuters/Daniel Munoz
To the brink.
NO GOING BACK

We admire mavericks, but the gene-editing scientist has gone too far

By Cassie Werber

The history of science is punctuated by people who went against the orthodoxy of their times. Galileo was hounded and imprisoned for his belief that the sun was the center of our galaxy. Charles Darwin offended a huge swathe of his Christian peers by coming up with the theory of evolution, in direct contradiction of the prevailing creation narrative.

Being a maverick, a rule-breaker with passionate conviction, is a quality lauded by the fiction we consume and the heroes we idolize, from James Bond onwards. But there are times, in science as in other disciplines, when breaking the rules doesn’t seem heroic. This week’s revelation that Chinese scientist He Jiankui used gene-editing to attempt to bestow HIV-resistance on babies is one of them.

He sidestepped his own field’s codes of practice to test a gene-editing tool called Crispr on two embryos that were then implanted, and carried to term, and are now living children. That individual decision, leaping as it does straight from theory and possibility to a genetic cliff edge, has raised some of the biggest ethical questions of our time.

It’s a stunning moment, and a deeply problematic one. In 2015, after the possibilities of Crispr became apparent, the scientists who developed the tool, other scientists who use it daily, and a dedicated group of bioethicists said that it shouldn’t be used in healthy human embryos until we know much more about the consequences. By He’s own admission, at a talk he gave on Wednesday in Hong Kong, neither Chinese authorities nor He’s own university sanctioned the work.

The mapping of the human genome, and the ability to then manipulate it—to create gene therapies for existing diseases, for example—is an example of science at its most awe-inspiring. Gene editing has been tested on human embryos before, though they weren’t brought to term. It’s also not the first time a genetically engineered child has been born.

Back in 2000, a baby was conceived using the sperm and egg of one set of parents, but some egg-cell components from another woman—specifically, the mitochondria, which act like the “batteries” in cells and contain a tiny number of a human’s 20,000 genes. The treatment rendered the baby resistant to devastating mitochondrial diseases. Since then some other children, though not vast numbers, have been born using that kind of splicing. The UK hands out licenses on a case-by-case basis for the procedure.

What is different in He’s case is that the result of this experiment is two living children who can pass on modified genes to their children, and their children’s children. It’s a fork-in-the-road moment: Never before has the human “germline”—the DNA passed from human to human through time—been changed by medical intervention.

Never before has the human “germline”—the DNA passed from human to human through time—been changed by medical intervention.

Chaos theory is most famously illustrated with an example of a butterfly. The insect beats its wings, causing a vibration so tiny it could barely be felt by a nearby fingertip; but the knock-on effect—without anyone being able to track how—causes a hurricane on the other side of the planet. Chaos theory warns humans off tampering with nature (most famously, perhaps, in the film Jurassic Park), because we don’t know what the effect will be.

In this case, however, there are some clues. The consequences could be indifferent, or good, or harmful: we might never know in our lifetimes. It’s the principle and what it means for coming generations—the possibility that we could make incremental but permanent changes without having stopped to work out all the possible ramifications—that makes people so nervous. Akshat Rathi gives a pertinent example in another article for Quartz:

Consider sickle-cell anemia, an occasionally fatal genetic disorder. Its genes, though clearly harmful, have persisted and spread because, while having two copies of the sickle-cell gene causes anemia, having just one copy happens to provide protection against malaria, one of the most deadly diseases in human history. Had we not known about their benefits, eliminating sickle-cell genes would have proved to be a bad idea.

Of course, there are some powerful counter-arguments. Science in general and medicine in particular are predicated on “tampering with nature”—testing and re-testing the world around us, and coming up with ways to tweak it for our own species’ advantage. Other scientists have pointed out that humans are constantly doing things that can mutate genes—like smoking or undergoing chemotherapy—and passing on mutations to their children. Others note that our genetic code has little impact on how we’ll ultimately turn out compared to the vast effect of other factors like parenting or wealth.

People who have suffered from, or have had children suffering from genetic disorders might well support the “maverick” in this case, seeing others’ qualms as the fastidiousness of people with the luxury not to be personally affected. There is also an argument that if legitimate science doesn’t explore and embrace what’s possible, the black market could (although black markets are adept at co-opting legitimate science as well).

These arguments can be convincing. But He’s break-away actions raise other ethical questions, too. Since the revelation of what his team actually did, a lot of questions have been asked about whether the patients in the trial were given adequate information about the nature of what they agreed to, and all its possible ramifications, known and unknown. He utilized tools that were available for a new purpose with far-reaching possible consequences; he did so in contravention of his field’s collective wisdom; and he may, possibly, have exploited his patients in the process.

Without buying into such hysteria, He’s action still cause a deep unease.

The hysteria around genetic modification once welled up around crops before subsiding (we grow and eat GM crops regularly). It crests around human children. There’s repugnance at the idea of creating desirable “designer babies,” in which someone, somewhere decides what “diversity” looks like. And there’s fear that, like Frankenstein, we’ll create monsters and not be able to control them. Such fears lead to extreme stances, such as opposition to in-vitro fertilization (which involves no genetic tampering), or to abortion on any grounds.

Without buying into such hysteria, He’s action still cause a deep unease. First, there is the question of whether He was simply seeking personal aggrandizement: A chance to play God, and be seen to play that role in the history of his field. Was the step he took in any way necessary?

The answer seems to be no. Modern medicine already has tools to stop HIV being passed on from parent to offspring. That means the gene edits He made, a significant intervention, could not be ethically or scientifically justified. When He was asked to explain his justifications at meeting in Hong Kong today, he deftly evaded the questions. It’s not yet clear how such an experiment could have ever taken place; what is clear is that the release of information was carefully orchestrated.

The second question is about choice. Unless coerced, no one can be compelled to undergo IVF, abortion, gene therapy, or any other medical intervention unless they choose to. But in order to make that decision an informed one, patients need every scrap of information about what’s happening before they undergo a procedure or take part in an experiment. Society also has a choice, but the alteration of the germline takes it away. The changes will enter our genetic makeup as a species. There is no return from that point of change.

We ask our scientists to push the boundaries of human knowledge, making discoveries that change the nature of what we know, and change what we do with that nascent knowledge. But, at the same time, we ask them to self-regulate, to follow guidelines, to listen to their peers and the public, to understand where the line is. It’s a delicate balance. We will all be affected, in the fullness of time, by the decisions made in He’s lab. And no one—including the scientist himself—knows how.