Gene editing is being sold on the promise of healthier babies — but what are the ethical concerns?

It has been seven years since Chinese biophysicist He Jiankui made an announcement that shocked the world's scientists.

He had made the world's first gene-edited babies.

Through rewriting DNA in twin girls' embryos, the man who would later be dubbed "China's Frankenstein" claimed he had made them immune to HIV.

But the experiment was swiftly condemned as "monstrous" and deeply unethical by a shell-shocked scientific community.

And He Jiankui was ultimately sentenced to three years in jail for violating medical regulations.

However, as the dust has settled in the years since, the race to advance gene editing has shown no signs of slowing down, spurred on by starry-eyed Silicon Valley investors, entrepreneurs and even pronatalists.

And by April this year, He Jiankui was back — announcing a new venture aimed at editing human embryos to create people resistant to diseases like Alzheimer's or cancer.

Months later, his ex-wife, Cathy Tie, unveiled Manhattan Project — the first company to publicly announce plans to create gene-edited babies, promising to prevent "thousands of diseases".

But although this science is advancing, it remains deeply controversial.

On the one hand, gene editing heralds hope of a future free from genetic disease.

But on the other, it strikes fears of a spiral into eugenics and so-called "designer babies".

Like 'installing a new app'

Gene editing tech first emerged in the 1970s.

It acts like scissors, snipping DNA at certain spots so scientists can erase, add or replace sections.

"It's as if you were given a new smartphone and you could never change it," Australian molecular biologist and genetics expert Merlin Crossley says.

"And then suddenly you had a way of installing a new app."

In 2009, a revolutionary new editing tool called CRISPR burst onto the scene.

Earning a Nobel Prize for inventors Emmanuelle Charpentier and Jennifer Doudna, it is simpler, faster, cheaper and more accurate than older tech.

But this breakthrough stoked fears about "designer babies" — embryos or fetuses whose genetic make-up has been purposefully selected or altered to achieve "desired" traits.

It sounds like the stuff of science fiction, but there have been broader movements in this space, in addition to He Jiankui's twins.

In 2009, a US fertility clinic announced plans to screen embryos for "cosmetic" traits like hair and eye colour, but suspended the service shortly afterwards due to backlash.

Meanwhile, in 2020, the first child was born following polygenic embryo screening, which estimates an embryo's chances of developing complex traits or health conditions influenced by thousands of genetic variations — not just a single gene.

In the end, baby Aurea's embryo was selected, as she had the best odds of avoiding future common diseases such as heart disease, diabetes and schizophrenia.

The company behind this, US-based Genomic Prediction, is not alone.

Several other commercial enterprises are cashing in on this space, screening not just for disease but also non-disease traits — such as height or IQ.

'It has the potential to save trillions of dollars'

While these programs have been met with significant resistance, not everyone thinks this science will be a poisoned chalice.

Julian Savulescu is an Australian philosopher and leading voice on the ethics of emerging technologies — in particular, new human enhancement and reproduction methods.

He says advances in the genetics space, including gene editing, could revolutionise health care — if done safely.

"It has the potential to save trillions of dollars globally and significantly prolong life and reduce suffering," he says.

Professor Savulescu believes "polygenic editing" — a theoretical form of gene editing that changes several DNA variants at once — is the future, with modelling showing it could significantly reduce the likelihood of certain diseases.

He and his fellow researchers predict this could become feasible in the next three decades — but he says there is still a lot of work to be done.

"Genes don't have just one effect, like cause diabetes — they have multiple effects at the same time," he says.

"You're not going to be able to just magically produce some valuable outcome without in many cases there being a downside to that."

Fears gene editing could reinvigorate social Darwinism

However, many others, such as Monash University philosophy professor Robert Sparrow, are worried about the future of this controversial space.

He fears gene editing could "reinvigorate social Darwinism" — the idea that people are poor not because of injustice, but because they are genuinely inferior in some way.

"People will insist that they want to remain tolerant towards some differences amongst human beings, but will try to eliminate differences in IQ or physical attractiveness," he says.

There is also a "clear danger" this tech could reinforce elitism, resulting in a two-tiered society where the rich can buy genetic advantages, Professor Sparrow says.

Professor Savulescu calls this the "Gattaca objection" — referencing a 1997 dystopian film about a future society where children are genetically selected to ensure the best traits.

"That's why you need to deliberately decide how you make [gene editing] available," he says.

"Is it available only through the market at a high price? Or should it be made a part of basic health care?"

There are also concerns this could be a slippery slope towards eugenics — beliefs and practices that aim to improve the "genetic quality" of a human population, now largely linked to the racial policies of Nazi Germany.

But Professor Savulescu argues modern clinical genetics is different.

"It's aimed at the wellbeing or health of the child themselves and it's voluntary whether parents take it and use it or not," he says.

"It becomes eugenic if it's made involuntary, if it's something that you have to do."

'It's not going to be designer babies'

No gene editing therapy for the treatment of humans has been approved in Australia yet.

You can face up to 15 years in prison if you make any heritable changes to a human genome.

Dianne Nicol, distinguished emeritus professor of law at the University of Tasmania, says there will have to be "a dramatic change to Australian laws" before this will change.

"But to my mind, it's a long way off," she says.

Safety remains one of the greatest obstacles.

In particular, there are serious concerns about "off-target mutations" — unintended genetic changes that can occur during gene editing.

"You can trial it in rabbits and primates but at some point you have to say, 'We're going to try it in human beings,'" Professor Sparrow says.

"And it's quite hard to know whether that's safe."

Professor Savulescu says it is anyone's guess how long it will be before polygenic editing becomes mainstream.

"Things either go much slower than predicted or much faster," he says.

Right now, most gene editing is in the "experimental lab space", according to Professor Crossley, but he believes this tech could be used to cure genetic diseases in babies in "less than 100 years".

As for fears about the future of genetics — Professor Crossley says people should not worry.

"There will be medical treatments," he says.

"But it's not going to be designer babies."