When you think of insecticides you probably think of dangerous chemical compounds that allow modern industrial agriculture (and its high yields) to occur, but that also have some negative effects on the environment and also on human/animal health. The effects of a certain class of insecticides on honeybees, for instance, may well be what comes to mind.
That’s now set to change, in the US anyways, as the US Environmental Protection Agency (EPA) has gone ahead and quietly and quickly approved the use of Monsanto’s “RNA interference” DvSnf7 dsRNA in a new product called SmartStax Pro — a line of genetically modified maize/corn seeds that are the result of a collaboration with Dow, that will contain the genes for Bt-toxin production as well as the DvSnf7 dsRNA.
So, to explain this more clearly — the US EPA has approved the use of DvSnf7 dsRNA in genetically modified maize/corn, which is intended to silence the functioning of key genes in the western corn rootworm, a major agricultural pest.
So, to say that again… what’s been approved is GMO maize/corn that is designed to actively interfere with the healthy functioning of another organism’s genome. In this case an animal, the western corn rootworm.
What unexpected effects will this have on animals that aren’t the the western corn rootworm? Who knows. I’m sure that Monsanto researchers don’t, though there will no doubt be claims to the contrary. Think of it as a massive uncontrolled experiment I guess… Something that can probably be said about much of the modern world.
To provide some context here, Monsanto’s last GMO maize/corn product, Bt-toxin producing corn, is fairly rapidly loosing its effectiveness due to the spread of Bt-toxin resistance amongst pests.
This is a situation that probably could have been slowed down to some degree by leaving enough of the non-Bt-toxin-producing maize/corn planted alongside the GMO crop that resistance didn’t spread so quickly amongst pests… but that’s not the way that things often work in the real-world (short-term profit maximization usually rules). In the real-world, though, the simple (and ancient) practice of crop rotation does go a long ways towards reducing western corn rootworm numbers. It’s rarely used in modern industrial-scale maize/corn agriculture, despite this reality. I guess that it’s easier to sell an idealistic and rose-colored (and dangerous) vision of the future than it is to learn from the maligned past?
The Atlantic provides more: “DvSnf7 dsRNA is an unusual insecticide. You don’t spray it on crops. Instead, you encode instructions for manufacturing it in the DNA of the crop itself. If a pesky western corn rootworm comes munching, the plant’s self-made DvSnf7 dsRNA disrupts a critical rootworm gene and kills the pest.
“This last step is called RNA interference, or RNAi, and the Environmental Protection Agency last week approved the first insecticide relying on it. Just a few years ago, RNAi was the hot, new biotechnology generating both hype and controversy. But its first approval as an insecticide has been surprisingly low-key. The EPA’s decision attracted little attention from the press or even from environmental groups that reliably come out against new genetically modified crops.
“RNAi is useful because it can be highly specific: It’s supposed to, in theory, turn off one specific gene in one specific species while leaving others unharmed. Plants and animals naturally use this process to ‘silence’ their own genes. And scientists have previously harnessed RNAi to create genetically modified crops, like apples and potatoes that don’t brown because their browning gene is silenced. With Monsanto and Dow’s genetically modified corn, however, the DvSnf7 dsRNA is actually silencing a gene in another living organism, the western corn rootworm. Rather than modifying itself, it modifies its environment.”
It should be realized here, though, that nothing in genetics is as simple as that — genes, and the wider organizational patterns that encompass them, interact in a vast number of ways, many of which are not obvious, and not intuitive. You can count me as a skeptic that genetic change can be effected so “cleanly.”
Back to the coverage from The Atlantic: “The Center for Food Safety, along with other groups, vocally opposed the apples and potatoes modified through RNAi. Bill Freese, CFS’s science policy analyst, admits they were caught a bit off guard by the EPA’s decision with RNAi in corn. The EPA only allowed for 15 days of public comment, and the agency did not post its proposed decision in the Federal Register. It’s not the first time the EPA has approved pesticides quietly like this, but Freese argues the unprecedented use of RNAi as insecticide should have merited more public scrutiny.
“The EPA was the last of three agencies — along with the FDA and USDA — that signed off on the safety of DvSnf7 dsRNA. Critics often point to a 2011 paper to question the safety of tinkering with RNAi. In that study, Chinese scientists found naturally occurring RNA molecules from rice circulating in the bloodstream of people eating it. That paper has gotten a lot of criticism, and scientists have had trouble replicating its findings.”
Freese argues though that the real issue here aren’t the potential effects on human health, but simply the reality that the GMO tech won’t even be effective over the mid-term (a point that is very true…): “There’s faddish interest in the latest technology. It often neglects the basic issues of the unhealthy practices used in planting corn.”
Which is a reference to the modern aversion to the use of simple practices that are known to be highly effective, even if perhaps inconvenient (and thus prone to lowering profits), such as crop rotation…
Monsanto reportedly expects maize/corn seed with RNAi to be on the market before the end of the decade. To be followed by RNAi soybean products, and an insecticide targeting the varroa mites that are often implicated in honeybee colony collapse disorder (as an element, not a sole cause, insecticides are often another element…).
Monsanto’s chief technology officer, Robb Fraley, was recently quoted as saying: “I would put RNA in the suite of really advanced, next-generation technologies that are adding to the excitement from a research perspective.”
In related news, a couple of recent studies have thrown a wet towel on many of the more “optimistic” claims made about the genetic engineering tool known as CRISPR — despite all of the fancy claims, it appears that there are significant barriers to its use as a means of introducing sterility into pest populations. The findings, though, pretty much relate to any animals with high genetic diversity amongst populations and/or those prone to inbreeding. (That wasn’t at first intended as a joke, but now that it’s been said…)
There’s a correlation to be made there to the infomercial-like claims made by Monsanto about its use of RNA interference sequences in genetically modified crops. How long will any perceived “advantages” last? Will the tech be used intelligently? Or with typical human shortsightedness? Is there an actual mid- to long-term advantage to its use? Or is it all just a sales gimmick?