Wednesday, December 26, 2012

What To Talk About When You're Talking About GMOs

Oh boy, the first ever genetically modified animal passed the last major regulatory hurdle, and presumably has the green light for FDA approval. AquaBounty Technology's AquAdvantage salmon will soon appear (unlabeled) in supermarkets and restaurants around the United States. Back in April, the FDA finalized its environmental assessment on the salmon, and finally released the results this past week, indicating that they see little risk of negative environmental impact. There's certainly valid reasons to make a personal decision to avoid this salmon, but I do want to try and separate the science from the science fiction to help you make a more informed decision about it. This seems like the perfect time to introduce the concepts and issues around GMOs as someone with personal experience in the lab with them, and, since at this point I think pretty much anyone who reads this knows me, you can vouch that I'm hardly a shill for Big Ag.

At 18 months, the transgenic fish is clearly much larger than the same-age normal fish. But overall growth of the same generation of fish evens out by 36 months. (Image Credit: Aqua Bounty Technologies)
To develop AquAdvantage, AquaBounty isolated the gene in the largest species of salmon, the chinook, that contributes to its size. Then, they inserted it in the genome of a wild Atlantic species to replace their own growth gene, allowing it to grow at twice its normal rate. However, this gene only affects the rate of growth, and does not create a new giant species of Atlantic salmon. Just by looking at the full-grown transgenic fish and a full-grown natural Atlantic salmon, you'd never be able to tell a difference. While I grant it may sound a little bizarre, and I definitely thought so about GMOs in general before I became more familiar with them, the techniques are hardly novel at this point. Every biology major for the last 30 years will likely have performed these techniques dozens of times. The ick factor, I think, comes from a misconception about what genes actually are, and an ethical issue of toying with nature that usually underestimates the prevalence of genes transferring from species to species. There's nothing wrong or shameful about this, really. It's more shameful that this information is so arcane.

Ultimately, the first issue comes down to the fact that DNA is DNA. Think back to your high school biology class, where you learned about its structure. It's the same stuff in every cell in my body, yours, and in the virus I got the other day that's really pissing me off right about now. A gene is basically a stretch of DNA that codes for a specific protein, with molecular switches nearby that turn it on or off. While this stretch of DNA, and the switches that make it up between species may vary in size and the precise code, there's nothing uniquely "chinook" about the chinook's DNA, just as there's nothing uniquely human about ours. Nobody is injecting any crazy new hormones into anything, it's simply replacing the existing hormone with a pretty similar new one using the existing one's own "machinery" to control its expression.
Who wants a tri-colored fish that was injected with some sort of red shit? (Image Source: Yvonnegraphy)
Because of all this, any stretch of DNA is theoretically fungible from species to species. Evolution occurs because the order of base pairs changes over time due to mutations, or perhaps from viruses leaving traces that get inserted into the host's DNA. Roughly 8% of every person's DNA initially came from viruses, just from natural gene transfer. That doesn't mean we're part virus, and it certainly doesn't mean that our ancestors were more natural humans. Nature is constantly changing and adapting to outside stimuli, and the adaptation happens at the DNA level. The concept of genetic modification is to preconceive these types of gene transfers, nothing more, nothing less.

Based on everything we know about molecular biology, chemistry, and toxicology, it just doesn't really make sense for GMOs, by definition and across the board, to present a public health issue, apart from the possibility that the specific novel protein the new gene encodes produces an allergic reaction. This is reflected in a broad consensus (AAASWHOsystematic review of 42 peer-reviewed studiesRoyal Society of Medicine) of science and health organizations around the world. I understand why many people do not trust this consensus. It's absolutely true that chemicals or pharmaceuticals once deemed completely safe by industry and regulatory agencies were later found out not to be so safe. I'm always very suspicious of industry, but I try not to let my suspicions replace or override evidence. Evidence is the sum of the best of our understanding about a particular topic, and while it can sometimes be incorrect or incomplete, in our case with GMOs the quality of the small amount of contradictory evidence is of very poor quality. I could write an entire post about the problems in a recent article that came out linking GMOs to cancer in rats that ultimately make this experiment of little to no value at all, but the conclusions it claimed to reveal will never fully disappear.

So, getting back to AquAdvantage, how exactly did this salmon pass an environmental assessment? The first question that needs to be answered is whether this new growth gene will escape into natural populations of Atlantic salmon. Now, think back to high school biology again. It's not enough for a gene to get passed on from a parent, the gene must provide a definite selective advantage to survive. It's plausible for quicker growth to be naturally selected for once it hits the ecosystem, but certainly not definite. The risk is real enough, though, that AquaBounty claims they will make, at minimum 95% of the transgenic fish sterile females that cannot possibly pass on the gene in question. Of course, while this does not completely eliminate the theoretical risk, it does reduce the probability of it actually occurring. To further reduce the possibility of a worst-case scenario, the fish will be bred at a facility in Prince Edward Island where, if they do escape, it will be very difficult for them to survive due to the extra cold winter temperatures and high salinity of the Gulf of Lawrence that they would escape to. Ultimately, this was deemed good enough by the FDA. If you have a quibble with the FDA, look at the study and determine how and why you think this is insufficient. They aren't going to listen to assertions and arguments without evidence.

That's the science behind GMOs, and none of what I said is all that controversial within the relevant fields. In the science bubble, these facts speak for themselves. It's a mistake, and a bit arrogant, to act as if that is or should be the case outside of science, in the court of public opinion as they say. Most people make decisions based on much more complicated factors, not the least of which are anecdotes that strike an emotional chord. Sticking only to arguments based in evidence doesn't really take those complicated factors into account. It's important to try and tell a compelling story, one that competes with powerful anecdotes, so my hope is that what follows below is a decent attempt at it.

To someone who uses evidence to guide decisions on science and technology, there is a bit of irony in labeling the political right as "anti-science", because we notice that for many on the left, science is more valid depending on whether or not corporations fight it or hold it up. We on the left are often amazed at the mass delusions the right has accepted as truth, from climate denial, to intelligent design, to conversion therapy to "save" people who "made the choice" to be gay. Unfortunately, we are not as critical of our own misconceptions, from the way we talk about GMOs, to not vaccinating our children. I don't think both sides are totally equivalent here, but they do all stem from a sometimes, but often not justified mistrust. It's a difficult thing to accept, but if you believe in science, you have to accept that this is not an appropriate lens from which to view biotech. I haven't read the full environmental assessment, and I'm certain there are valid criticisms to be made from it; there always are. However, none of them amount to a (albeit probably half-serious) headline saying "The Apocalypse is Here". I think we have the capacity to be a whole lot more rational than the current makeup of the right wing, but this requires examining our own thinking and being secure enough to accept that maybe our gut reactions are leading us to places that aren't totally justified. While it's totally OK to have a visceral reaction to an article saying this fish will destroy humanity, I hope your next reaction is questioning whether those emotions are closing you off to accepting more information that makes things a bit more complex. That is totally not OK, because very little in the world is purely black and white. It wasn't the case when George W. Bush was saying "you're either with us or you're against us", and it's not the case when thinking about organic vs. industrial agriculture.

While Monsanto is certainly is prone to exaggeration, unethical business practices, and are one of the largest contributors to an unsustainable food system, this does not undo the science on their side about GMOs. Technology pretty much always comes with some risk and some benefit, and the question is always whether the benefits outweigh the risks. Often, it seems that the only benefit is in the bottom line of the company that develops the GMO, and AquAdvantage is not really an exception. The benefits do go to AquaBounty, but I think what tends to get overlooked is that fish farmers who can cycle out their enclosures more quickly will also perceive a benefit. There's plenty of family farmers who actively choose to use Roundup Ready corn because they perceive it to be a more reliable means to provide for their families. I may not want to support either one with my own money, because I don't want to support "conventional" agriculture, and I don't approve of fish farming, but I'm an unapologetic pragmatist. The burden is on us to demonstrate a better way accepting that economics matter, and they matter from a self-interest point of view. I don't want to force someone to be more environmentally responsible with no assurance that their ability to finance their huge, expensive equipment is safe, and I don't want to advocate for any sort of policy that is based more in ideology than evidence. Most of these farmers are heavily in debt and make short-term economic decisions because of it, so make your solution more enticing from a short-term economic point of view. Demonstrate the utility of your solution, and do it without expecting much help from government. We really need it.

Right now, scientists are working to develop drought-resistant GMOs that can survive dry spells like we went through in the Midwest this past summer, and also require less irrigation and conserves our aquifers. There's also a group working on crops that use less nitrogen, potentially minimizing the use of synthetic fertilizers made from petroleum, and thus reducing the type of agricultural runoff that has created a giant dead zone in the Gulf of Mexico. Some of these issues could possibly be helped by conventional breeding, but compared to genetic engineering it's less efficient in time and money spent. It's certainly possible that neither GMO ever pans out at all. Sure, the ideal solution is to grow our food in a diverse field, without monocropping and synthetic inputs, but I don't see much value in dismissing something that tries to improve the latter issue without forcing farmers to adopt an entirely new and economically unproven method. We certainly are willing to give electric vehicles time to develop, knowing full well that they are mostly impractical right now, while the electricity is still mostly generated by fossil fuels. They are nowhere near their potential, and even the biggest cheerleaders acknowledge this. Same goes, I think, for GMOs. Monsanto doesn't help by insulting our intelligence and acting as if the potential has arrived, but really, what does that even matter? Nobody really believes that. Why would we want to dismiss GMOs like these out of hand because of the techniques used to create them? Are there really more barriers to competition in biotech than any other industry, where the companies involved now will always control it? Just think about where IT once was. In 20 years, I have little doubt that we'll know full well where biotech stands, and today will be looked back upon like the 1960s are in IT, just replace IBM and Bell with Monsanto and Cargill. They'll lose control, because big corporations are good at using influence and access to maintain their market share, but not through innovation. That's where the proverbial college dropout in his or her garage comes in, and they'll most definitely be coming.

Please don't be afraid to comment on this post if you disagree. I'm happy to engage with people who think I'm crazy.

No comments:

Post a Comment