We tend to imagine that scientists know exactly what they're making. So it's oddly reassuring — and a little head spinning — to learn that one of the first challenges facing a National Academies committee on synthetic cells was simply agreeing on what a synthetic cell actually is.
That was the starting point for our conversation with Emma Frow, an associate professor at Arizona State University whose work sits at the intersection of bioengineering, science and technology studies, and the governance of emerging biotechnology. Emma served on the committee behind a recent consensus report on the responsible innovation of synthetic cells, and she described spending months wrestling with definitions before any other questions could even be asked.
A spectrum, not a thing
The reason is that "synthetic cell" isn't one technology, is because it is a spectrum of different variations and combinations. At one end is a simple membrane enclosing a handful of enzymes — something that may not be alive in any conventional sense, and that exists in a genuine regulatory gray zone between chemical and biological oversight. At the other end is the long-standing scientific ambition of building a living, replicating cell more or less from scratch. In between are the practical applications driving much of the field: programmable cells for drug delivery, biomanufacturing in bioreactors, and biological substitutes for agricultural chemicals.
Emma offered two clarifying questions that help locate any given creation on that spectrum: Does it contain genetic material? And can it replicate? Those answers shape everything about how seriously, and in what way, we ought to pay attention.
The mirror in the lab
The conversation's most striking turn concerned "mirror life" — organisms built from the reversed molecular handedness of all known biology. Every living thing we've found uses left-handed amino acids and right-handed DNA. A mirror organism would invert that. For years this was framed as a potential safety feature: something so alien it couldn't interact with existing life. But the scientific community has since questioned that assumption, and in late 2024 a group of leading researchers called for restraint, warning that a self-replicating mirror cell could pose risks we'd have no evolutionary defense against.
Care as an ongoing practice
What gives the episode its center of gravity isn't the specter of catastrophe. It's Emma's insistence that care isn't a box you check once. It's a posture you maintain throughout the work — and one the biotech community, by necessity, has cultivated more deliberately than some faster-moving fields. Biology resists the move-fast ethos. There is no perfect containment, and some experiments can't be undone.
The result is a conversation less about prediction than about practice: how thoughtful people decide what's worth building when the old categories no longer hold.
