A scientist adds a few chemical compounds to a bubbling beaker and gives it a swirl. Subtle reactions occur, and, lo and behold, a new life-form assembles itself, ready to go forth and prosper. Such is the popular imagining of synthetic biology, or life created in the lab.
But researchers in this field are not as interested in animating the inanimate. In fact, scientists remain far from understanding the basic processes that could allow inert, undirected compounds to assemble into living, self-replicating cells. The famous Miller-Urey experiment of 1952, which created amino acids from primordial goo, remains difficult to replicate conclusively.
Rather synthetic biology today is about modifying existing organisms. It can be seen as genetic engineering on steroids: instead of replacing one gene, synthetic biologists modify large chunks of genes or even entire genomes. The change in DNA can force organisms to churn out chemicals, fuels and even medicines. “What they’re doing is constructing from scratch the instruction set for life and adding that to something already alive, replacing the natural instruction set,” explains biological engineer Drew Endy of Stanford University. “It defines an alternative path forward for promulgating life on earth. You no longer need to descend directly from a parent.”
In that regard, some scientists do not see any reason to replicate an existing cell with a man-made one. “Making something as close as possible to an existing cell, you might as well use the existing cell,” argues geneticist and technology developer George M. Church of Harvard Medical School. And manipulating genomes has become so widespread that even high schoolers do it.
Synthetic biology, in fact, is all about bringing the principles of large-scale engineering to biology. Imagine a world where bamboo is programmed to grow into a chair, rather than roughly woven into that shape through mechanical or human industry, or where self-assembling solar panels (otherwise known as leaves) feed electricity to houses. Or trees that exude diesel fuel from their stems. Or biological systems that are reengineered to remove pollution or to thrive in a changing climate. Reprogrammed bacteria might even be able to invade our bodies to heal, acting as an army of living doctors inside us.
“In principle, everything that is manufactured could be manufactured with biology,” Church argues. It is already happening on a small scale: enzymes from high-temperature microbes used in laundry detergent have been reengineered to perform in cold water, thereby saving energy.
Synthetic biology “is going to fundamentally change the way we make everything for the next 100 years,” predicts David Rejeski, director of the science, technology and innovation program at the Woodrow Wilson International Center for Scholars in Washington, D.C. “We can engineer matter at a biologically relevant scale. That’s as big a change as the industrial revolution back in the 19th century.”
With great promise comes great risk, too—namely, in the form of modified organisms escaping the lab. Most such creations today are too ungainly to survive in the wild. For more sophisticated creations in the future, synthetic biologists expect that various safeguards would need to be instituted, such as strict monitoring or a kind of self-destruct sequence in the new genetic code. Because scientists can entirely remake organisms at the genetic level, they can insulate them from natural systems, Endy says: “We can make them fail fast.”
Nevertheless, some scientists are indeed attempting to re-create life. Carole Lartigue, Hamilton Smith and others at the J. Craig Venter Institute have made a bacterial genome from scratch and even turned one type of microbe into another. Researchers elsewhere have created synthetic organelles and even an entirely novel organelle, the so-called synthosome, to make enzymes for synthetic biology. Life from scratch may be imminent.
Such a feat does not mean scientists will understand how life arose in the first place, but it might provoke fears that humanity has achieved the undeserved power of deities. But the creation could also have a more humbling effect—by transforming our understanding of our fellow life-forms. “The benefits would be to remake our civilization in partnership with life at the molecular level to sustainably produce the materials, energy and feedstocks we need,” Endy says. “We will have a balance of partnership with the rest of life on the planet in a way that is very different from the way we now interact with nature.”