We certainly don’t pause to consider that, thanks to the trillions of bacteria we host, most of the genetic information in our bodies is not actually human. We’re a composite organism. Life is basically the weirdest and most astonishing thing ever.
And now, increasingly, human beings are at the controls – through genetic engineering and other advanced laboratory technologies. This is the age of “synthetic life.”
GMOs (genetically modified organisms) are a source of enduring controversy, and it’s not simply a matter of science. There are economic and political issues here, with huge corporations like Monsanto looming over a discussion that touches on ownership of novel species and the question of who, exactly, will benefit from these technologies.
But let’s cut to a basic question: Are GMOs safe?
Nothing controversial there! Seriously, you can answer this question round or square depending on which experts and activists you contact. Generally, though, scientists hold that food containing GMOs are just as safe to consume as food that comes from crops modified through traditional breeding techniques. Just because it comes out of a lab doesn’t make it dangerous. The American Association for the Advancement of Science opposed the 2012 Proposition 37 California referendum that would have required GMO labeling. The AAAS board of directors said this would unnecessarily alarm consumers.
But what about the environment? Do GMOs pose an ecological risk?
“The answer to that is controversial,” said David Guston, a professor of politics and global studies and co-director of the Consortium for Science, Policy and Outcomes at Arizona State University. He noted a much-publicized case where “superweeds” had developed a resistance to the herbicide Roundup as a result of heavy Roundup use on genetically modified, Roundup-resistant crops.
“Any particular change is part of a larger system. You can say that the Roundup-resistant weeds, the superweeds, aren’t a direct effect of the genetic modification of the BT-resistant corn, but they’re a consequences of the agricultural practices that surround the Roundup-ready crop,” Guston said. “Some of this is foreseeable, and some of this is not foreseeable.”
In their 2012 statement, the AAAS board of directors offered a much stronger endorsement of GMO crops:
“[T]he science is quite clear: crop improvement by the modern molecular techniques of biotechnology is safe. Rather, these initiatives are driven by a variety of factors, ranging from the persistent perception that such foods are somehow “unnatural” and potentially dangerous to the desire to gain competitive advantage by legislating attachment of a label meant to alarm. Another misconception used as a rationale for labeling is that GM crops are untested.”
Now let’s talk about the latest news. Last week we reported on two papers in Nature describing breakthrough techniques in modifying E. coli bacteria to ensure that they would be unable to thrive if they escaped containment. These genetically modified bacteria have been designed to be virus-resistant. They’ve also been engineered to require a synthetic amino acid to stay alive. That amino acid doesn’t occur in the natural world. This would, in effect, keep the microbes on a leash. It would also, according to one of the scientists, George Church, make such bacteria attractive to industries that want to use them to make chemicals or clean up toxic waste sites.
But there are skeptics, including Denise Caruso, author of “Intervention: Confronting the Real Risks of Genetic Engineering and Life on the Biotech Planet.” She told that it’s hard to measure accurately the risks posed by genetically engineered microbes.
“Microbes are opportunistic. Bacteria. Viruses. They want to stay alive, and they will, given incredible odds against them,” she said.
[At the risk of revealing too much about how the sausage is made: I had considered a possible lede (yes, that’s how we spell it in the news business) that quoted the Jeff Goldblum character in Jurassic Park in the scene where he’s skeptical that all dinosaurs have been engineered to be sterile: “Life, uh…finds a way.” I didn’t go with that, but sure enough, our readers immediately posted links to that scene.]
A different objection to the new research came from Steven Benner, Distinguished Fellow at the Foundation for Applied Molecular Evolution in Gainesville, Florida. He said the new technique solves a non-existent problem.
In an e-mail, Benner wrote that life has evolved to fill every ecological niche where energy and water is present:
“In doing so, [organisms] do an excellent job of “local optimization”. That is, if any mutation would allow them to grow faster in that environment, it would have emerged, and would (in fact) have taken over this environment. This is, of course, more or less clean Darwinism (and the details that are included in the ‘more or less’ caveat would not interest your readers). It is like climbing a fitness landscape; natural Darwinism has gotten to the local top of Mount Hood. Any step away goes downhill, in fitness.
“This means that any genetically modified organism (GMO) is less fit, less able to survive, get married, and have children in any natural environment. Different if the environment is doused with herbicides; then the plant having an herbicide detoxifying gene is fitter. But remove the herbicide, and the native strain will take over (if it is still around). That is, if you are worried about damaging an ecosystem, you worry about the herbicide, not the GMO.”
Church responded by e-mail:
“I agree with Steve (and most GMO industry leaders) that current GMOs (and domesticated organisms in general) won’t survive long in the wild. But multi-virus resistant GROs are very likely to be an exception (and an industrially attractive one at that)….We wanted to get the safety part in place before we take the next step in making full resistance to all viruses. Right now we have modest resistance to two viruses/phages that we have inspected in detail.”
Church made a comparison to automobile accidents in 1902. Yeah, it didn’t seem like a big problem at the time, because there weren’t many cars. But let’s put in the safety features now.
In a separate e-mail sent after he read the Nature papers, Steven Benner offered some additional thoughts:
“The American body politic has difficulty understanding risk. In fact, by any standard of risk, genetically modified organisms pose no risk at all. These two papers begin by denying this fact. Thus, their difficult technological work has no purpose.
“On the contrary, by asserting in a prominent place (the journal Nature) that this non-existent risk needs solution, these papers subtract from the ability of the body politic to do sensible risk assessment to create sensible public policy.
“Public policy still needs to recognize the impact of technology. Crops and bacteria have been genetically modified by human activity for thousands of years, without recombinant DNA technology, by people whose names you might recognize (Luther Burbank and Nobel Laureate Norman Borlag).
“As their principal impact on the biosphere, GMOs over the millennia have allowed more humans to exist on Earth with better health for longer lifespans. This has had a clear impact on the global environment.
“However, here, policy prescriptions must reflect social values and goals; they have nothing to do whether the technology used to achieve these involves recombinant DNA genetic modification, or classical tools for genetic modification.”
Obviously this is not the end of this very important conversation, and perhaps Benner and Church and others need to sort out some of these issues. But to get back to my throat-clearing opening up top: Benner makes an important and rather humbling point that bears on any discussion about genetic engineering, which is that the Earth is already full of such engineering — naturally, incontrovertibly, implacably. It’s not deterministic.
Life, writ large, conducts experiments without our permission. We don’t even realize these experiments are happening. Do your own risk analysis on that.