Reconsidering “Mirror Life”
July 18, 2025
Just as humans have left and right hands that are mirror images of one another, the molecules in our cells have similar properties. Proteins, for instance, are composed of “left-handed” amino acids. Using molecular engineering, scientists could conceivably create amino acids that are “right-handed,” or produce other biomolecules that mirror their existing counterparts. Such research into so-called mirror life could spur the development of new drugs and other innovations.
Concerned about possible risks, including “pervasive lethal infections,” a group of authors in Science magazine recently recommended “that research with the goal of creating mirror bacteria not be permitted, and that funders make clear that they will not support such work.”
In Issues, John H. Evans, Craig Callender, Neal K. Devaraj, Farren J. Isaacs, and Gregory E. Kaebnick argue for a more nuanced approach to this nascent field: “What’s needed is a clear, practicable line that can be applied to relevant research and assure scientists, funders, and the public that work does not violate an ethical norm.” They outline the decision points that could help evaluate precursor research into mirror life—allowing for discovery and innovation while mitigating potential harms.