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Dozens of scientists are calling for ban on the creation of “mirror life” microbes used in research because they present an “unprecedented risk” to life on Earth. They believe these microbes could lead to a lethal infection in humans, animals, and plants.
The scientists explained their concerns about “mirror life” microbes in a a 299-page report published in the journal Science on Thursday. “Mirror life” microbes, or “mirror bacteria” are constructed for research purposes by using mirror images of molecules already found in nature.
“All known life is homochiral,” the scientists wrote in their report. “DNA and RNA are made from ‘right-handed’ nucleotides, and proteins are made from ‘left-handed’ amino acids. Driven by curiosity and plausible applications, some researchers had begun work toward creating lifeforms composed entirely of mirror-image biological molecules. Such mirror organisms would constitute a radical departure from known life, and their creation warrants careful consideration.”
They go on to explain why the creation of these “mirror bacteria” has the potential to have a devastating impact on humanity and all other life on Earth.
“Our analysis suggests that mirror bacteria would likely evade many immune mechanisms mediated by chiral molecules, potentially causing lethal infection in humans, animals, and plants,” the scientists wrote. “They are likely to evade predation from natural-chirality phage and many other predators, facilitating spread in the environment.
“We cannot rule out a scenario in which a mirror bacterium acts as an invasive species across many ecosystems, causing pervasive lethal infections in a substantial fraction of plant and animal species, including humans. Even a mirror bacterium with a narrower host range and the ability to invade only a limited set of ecosystems could still cause unprecedented and irreversible harm.”
“The threat we’re talking about is unprecedented,” said Prof. Vaughn Cooper, an evolutionary biologist at the University of Pittsburgh. “Mirror bacteria would likely evade many human, animal and plant immune system responses and in each case would cause lethal infections that would spread without check.”
Two of the scientists, synthetic biologists, Dr. John Glass and Dr. Kate Adamala, wrote about their concerns for The Scientist.
Microorganisms developed in laboratory settings are typically grown in highly specific conditions and with very particular nutrients whose composition and concentrations do not reflect the complex and diverse conditions found in nature. As a result, while laboratory breaches unfortunately do happen—with hundreds of “possible release” events per year leading to at least one or two detected infection events per year—most of those involving artificial or modified organisms do not result in an outbreak, as they are too “fragile” to thrive in the adverse environment of the outside world, making them easy prey to natural predators such as viruses that target bacteria (bacteriophages).
However, many interactions between organisms and cells depend on being able to sense and react with chiral molecules in the first place. Their incompatibility with natural biological reactions would leave mirror bacteria with no natural predators in the wild, as they could not be sensed, killed, or digested by bacteriophages or other organisms. Crucially, many of the immune responses in humans, other animals, and plants also work by sensing and reacting with chiral bacterial molecules. If a human were to be infected with mirror bacteria, it could be as if they were immunocompromised, as their immune systems would face great difficulty in detecting or killing the mirror cells. As a result, mirror bacteria could hypothetically replicate to extremely high levels in the human body, causing conditions similar to septic shock.
“We should not be making mirror life,” Adamala told The Guardian. “We have time for the conversation. And that’s what we were trying to do with this paper, to start a global conversation.”
The scientists conclude in their report, “Unless compelling evidence emerges that mirror life would not pose extraordinary dangers, we believe that mirror bacteria and other mirror organisms, even those with engineered biocontainment measures, should not be created. We therefore recommend that research with the goal of creating mirror bacteria not be permitted, and that funders make clear that they will not support such work.”