Of Microbes and Men

It is a cliche in commentary on synthetic biology that there is no universal agreement on what synthetic biology is. Some see it as an incremental extension of earlier genetic technologies for modifying organisms. Others see it as the beginning of real genetic engineering, on the grounds that what has passed for "genetic engineering" up until now has been too haphazard to merit the term. The very grandest definitions of the field, on the other hand, do not limit it to any particular technology; they describe the field simply as a matter of designing and constructing biological systems for useful purposes. (1) Given the disagreement about what synthetic biology is, we might expect a similar range of views about whether it should be done. Some of the earlier, simpler technologies for genetic engineering struck some critics as deeply troubling, on grounds that they represented an intrinsically unattractive change in the human relationship to nature, while others found them entirely unexceptionable. On the face of it, if synthetic biology is real genetic engineering, then there should be an even deeper rift about synthetic biology. But in fact, there may be an emerging consensus, articulated by the Presidential Commission for the Study of Bioethical Issues, which found that "opposition to synthetic biology at present on such grounds alone [that is, on grounds that it is intrinsically troubling] does not adequately reflect the relationship of this technology to previous scientific activities and the current limited capabilities of the field," but that the concern should be "revisited periodically as research in the field advances in novel directions." (2) Surely the technology touches a sensitive spot. Many people feel that the alteration of nature should have limits of some sort--witness the earlier opposition to genetically modified organisms and more than a little of the concern about the environment. Concerns about the protection of endangered species and "wilderness" areas are perhaps the clearest examples of it. Synthetic biology is thus a new topic in a growing debate about which of two competing ideals should guide the human relationship to nature. As articulated by Bruce Jennings, a scholar at the Center for Humans and Nature and a participant in a two-year research project at The Hastings Center on the ethical issues of synthetic biology, one ideal is characterized by a discourse of "altering nature to meet human demands," and the other by a discourse of "adjusting human demands to accommodate nature." (3) The former holds that nature is no more than stuff to be put to use--to be pumped out of the ground, cut down, burned, turned to waste, and disposed of as needed. The latter calls on us to cherish the natural world as it is and limit the harm humans are wreaking on it--not just in order to keep the planet habitable for humans as long as possible, but because the planet, with its diversity of life, is valued in its own right. Synthetic biology seems in some ways to be the nonpareil example of the "altering nature to suit human demands" ideal. I am in the accommodate-nature camp: at least, I would not want to go too far in the direction of altering nature to suit human demands. But as the commission--along with many others before it--points out, we all accept some manipulation of organisms and some adjustment of nature. Medicine is nothing if not manipulation of organisms, and farming nothing if not adjustment of nature. The question, then, is how to balance these ideals when we face specific instances of synthetic biology. For me, that decision is not clear, my preference for accommodating nature notwithstanding. Part of the issue is what the commission called "the current limited capabilities of the field." Whatever general definition we adopt for synthetic biology, a plausible working definition of it for now is that it has to do with various strategies for modifying or synthesizing the genomes of microbes, along with some more exploratory research on new ways of building some of the basic parts of microbes, all with the goal of creating microbes that are useful for industrial, medical, or other purposes. …