We are all used to sensationalist headlines about a disaster Or another on the horizon. So I don’t blame anyone who was exhausted when they saw last month that dozens of scientists warned in the magazine Science that mirror bacteria could cause a catastrophic ecosystem collapse and even mass extinction.
After all, we already face imminent threats such as H5N1 to worry aboutand more generally, we live in an era which, as Adam Kirsch said I recently put it in The Atlantic, it feels like “an apocalypse, constantly.” The news about mirror bacteria came the same week we were told that a widely read paper study the way our black spoonbills were killing us was really just the result of a mathematical error. It can be difficult to distinguish which concerns are extremely serious and which are just headlines that will be forgotten a month later.
But after reading a lot more about the mirror bacteria situation, I’m here with some bad news: It’s real and it’s really serious.
More than 35 scientists, including renowned researchers in half a dozen different fields, gathered for a December technical report to claim that ongoing work on mirror bacteria could trigger a mass extinction. The catastrophe he warns against is plausible, even if it is hallucinatory.
And this isn’t one of those situations where skeptics come in from the outside: many leading scientists who worked on the invention of mirrored life are now convinced that such work would be incredibly dangerous. In fact, this is one of the rare cases where experts became more concerned as they learned more, instead of less concerned.
But there is also good news: now that we are aware of the risk, disaster should not occur by accident. At this point, the mirror’s life is mostly theoretical: it would take decades of work to actually create it. So, as scientists look more closely at the risks, they will be able to bring this work to an end, with very little cost to other essential research.
And with scientists from many disciplines expressing concerns, there’s a good chance we can just agree, as a world, to do the right thing and just not go for it. This is ideally how we should manage new existential risks.
Think of the letter R and its mirror image, the letter Я. No matter how much you spin the letter R on a two-dimensional page, you will never get an Я. If you build a protein intended to bind to an R, an Я will not fit and a molecule will turn out differently if it uses an R or a Я as its backbone.
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This is the central concept of mirrored life, albeit in three dimensions rather than two. The amino acids that make up the proteins that constitute all life on Earth can form from atoms in two different mirrored ways, colloquially “left” and “right.” But even though molecules exist in both forms, all life on Earth builds proteins only from left-handed amino acids (and most other biomolecules, like DNA, also have a “hand” – which is why the DNA spiral helix always goes one direction.)
This poses a tantalizing scientific puzzle: Couldn’t you, in principle, construct a “mirror life” – a life made of right-handed amino acids? This would be a huge engineering project, involving work that we do not yet know how to carry out.
But in principle it should be possible. We have already constructed mirror proteins and mirror enzymes that can read mirror genes.
What could go wrong?
The question is what would happen once you successfully build a mirrored life.
At first, it was thought that mirror bacteria would actually be harmless, because they cannot digest most of the “normal” molecules that make up all existing life. Of course, they could eat simple nutrients, which do not have the “manity” property. But would that be enough to allow them to multiply and spread?
Many scientists initially assumed that this would not be the case, meaning that mirror life would be safely self-limited, unable to spread too far because it would be unable to digest the rest of life, including the human beings.
But as they explored this possibility, experts became concerned that it might not be true. “Contrary to previous discussions of mirror life, we also realized that generalist heterotrophic mirror bacteria could find a range of nutrients in animal hosts and the environment and would therefore not be inherently bioconfined,” the study explains. Science report find.
Thus, the mirror bacteria would finally be able to find enough to eat. Worse still, existing life would struggle to eat them. This means that creating mirror bacteria could be a bit like introducing an invasive species into an ecosystem (in this case, the entire planet) where it has no predators.
Without anything initially evolving to eat or counter it, it could likely spread quickly. Invasive species can be very difficult to eradicate, even if they do not reach very high populations. Mirror bacteria may well look like this: a new species of globally distributed environmental bacteria, alongside a multitude of existing bacteria.
But how catastrophic would the introduction of this new invasive species be? Humans (and other animals and plants) are constantly exposed to environmental bacteria, and these are generally not a problem unless, for example, you have a damaged immune system.
A team of immunologists therefore looked into the question of whether our immune system would react appropriately to an invasion of mirror bacteria. Worryingly, they concluded that this was unlikely to be the case.
While some of our immune defenses work without specific targeting of a particular pathogen, many of them only work by locking onto the invading pathogen – something we would not be able to do for bacteria mirrors. And scientists didn’t just discover that it could make humans sick. For exactly the same reason, this could do everything else sick – every animal, even plants, can be vulnerable (although there is substantial variation in the exact susceptibility of each species).
The result, according to the December report of Sciencecould be terrifying.
“We cannot rule out a scenario in which a mirror bacterium acts as an invasive species in many ecosystems, causing widespread fatal infections in a substantial fraction of plant and animal species, including humans,” the authors found, saying that a plausible outcome was “unprecedented and irreversible harm.”
“It is difficult to exaggerate the seriousness of these risks,” says an immunologist. Ruslan Medjitovone of the co-authors of the technical report, warned in a press release sent to me. “Living in an area contaminated with mirror bacteria could be similar to living with severe immune deficiencies: any exposure to contaminated dust or soil could be fatal. »
“We’re not going to do it.”
To be clear, there were many good reasons to consider creating a mirrored life. “It’s inherently incredibly cool” Kate Adamalaa synthetic biologist at the University of Minnesota, explained to the New York Times the efforts to create mirror bacteria. “If we had created a mirror cell, we would have created a second tree of life.”
Indeed Adamala and three other scientific colleagues are the beneficiaries of a 2019 scholarship in which they explained that they “seek to safely design, construct and deploy synthetic mirror cells.” But as they delved deeper into the issue, through collaboration on the 299 pages technical reportshe and her colleagues became convinced it wasn’t worth it: All four have now joined the call in Science for the work to be stopped. “We say, ‘We’re not going to do it,’” Adamala told the Times.
The U.S. government, which funded Adamala and his colleagues’ work to build a mirrored life, is also adapting in response to this warning.
“We appreciate the efforts of these scientists to identify and assess the potential future risks of this type of synthetic organism…Advances in the life sciences and related technologies now empower scientists in ways that were barely imaginable a long time ago. only a few decades,” a spokesperson said. the White House Office of Science and Technology Policy told me.
“These advances have remarkable potential for benefit and, as these scientists have made clear, they can also cause significant harm. Given the potential risks, we will work with and within the global research community to avoid and mitigate risks while protecting the potential benefits of research in other applications of synthetic biology. The U.S. Government is beginning a deliberative process to review scientific assessments of the implications of mirror life and, where appropriate, develop or revise relevant federal biosecurity policy.
For this reason, I think this can be read not as a pessimistic title to start your year, but as a hopeful story. A huge number of talented people from different relevant disciplines got together and tried to figure out if there was a problem. They realized this was the case and changed course.
Of course, it is too early to declare victory. But while it’s a looming challenge, it’s also the story of people stepping up to the plate – long before disaster strikes.
A version of this story was originally published in the Future perfect bulletin. Register here!