Allison Snow at Ohio State University, a leader in research on genetically modified plants and their environmental impacts. How scientists hope to address fears about “g.m.” crops with research. Snow began her career studying how pollen — and genetic information — spread from one plant to another.
She began to wonder if pollen from genetically modified crops might be able to fertilize weedy relatives in the wild. A common fear of environmentalists today is that genetically modified crops might ultimately produce “superweeds.”
Using greenhouses and isolated plots of land, Snow’s team crosses so-called “g.m. crops” and their weedy relatives to study genes are transfer. In one experiment, they crossed domestic sunflowers — with gene added to resist insects — with wild sunflowers. The resulting hybrids did grow better and avoided insect damage. Snow told us that she was surprised by the hybrids’ heartiness — but she doesn’t like the term “superweed.”
Allison Snow: I think that some genetically modified plants will be perfectly safe and others could potentially cause health problems or environmental problems. And I don’t like to put them all in one category. I think some will be fine and we just have to be careful about releasing new types that come along because once they’re released, you can’t take them back. . .
Snow says that her current research can be boiled down to trying to answer two basic questions — how easily do crop genes get into wild populations? — and what difference does it make? In other words, when genes are transfered from crops to weeds, does it produce a more robust weed?
Though Allison Snow’s research has plenty of important environmental and political implications, her underlying interest in transgenics began as a pure appreciation for the wonders of biology.
“I’m still amazed that you can take a gene from a jellyfish, put it into a plant, and make the plant glow in the dark!” she wrote in an e-mail. “You could even design an artificial gene that works better than any naturally occurring genes.”
But with knowledge, she believes, comes responsibility. “Because this technology is so powerful, I’m very eager to inject ecological and evolutionary thinking into the design of GMOs. It worries me that many molecular biologists do not have any training in ecology and many ecologists do not understand molecular biology.”
Snow’s research is watched closely by several federal agencies in the U.S., including the Department of Agriculture, the Environmental Protection Agency, and the Food and Drug Administration.
For the past decade, Snow has been filling the scientific literature with studies about how easily genes can move from crops to weeds. In recognition of the importance of her research, Scientific American named her one of the top 50 research leaders of the year in 2002.
The experiments Snow conducted on sunflowers were limited. They only lasted for a year and involved small plots. At that point, she published some preliminary results that raised a red flag — the resulting hybrid weeds looked like what some environmentalists might call superweeds. Snow is concerned, but won’t go so far as to call them superweeds. She says more extensive experiments would have to be carried out to determine what impact these weeds might have on the environment.
Snow would like to do larger scale studies, but the biotech firms that own the patents for the transgenic sunflowers are blocking such an effort. Snow says that the companies decided not to commercialize the transgenic sunflowers, so the possible environmental impacts are no longer a concern. But she says it is a major problem in her field that companies can patent genes and then use the patent to prevent research into the environmental impact of using that gene.
More about “Superweeds”:
No discussion of Allison Snow’s research is complete without mentioning “superweeds” — even though she tries her best to avoid using the term. “It got into the news so often, that it’s out there,” she says. “To me, it’s just a metaphor for the problem of having weeds that become more vigorous, which might happen more easily with transgenes than with what’s been available in the past — just normal crop genes.”
So far, one reason genetically modified crops haven’t caused too much trouble in the U.S. is that the main transgenic crops — cotton, corn and soybean — don’t have weedy relatives here. But in Mexico and China, for example, that’s not the case.
Snow emphasizes how important it is to study one crop at a time. “We tend to focus on case-by-case because each case can be different,” she says. “But the general question is: ‘Could those crop genes make the weed a lot bigger problem than it already is?’ ”
The answer to that question is not so simple. For each crop — from corn to soybeans to radishes to sunflowers — researchers have to look at a variety of questions, like: How easily to crops mix with wild relatives? How likely are genes to persist in the weedy plants? Is pollen from transgenic crops more potent than pollen from normal crops? And does an increase in seed production translate to a more ubiquitous weed? So far, answers seem to vary among crops and genes involved. And Snow’s research is most relevant in places where crops and their weedy relatives actually grow near each other.
“As much as people want to generalize, it’s good to get specific and ask what are the worst-case scenarios, and what are the questions that we need to study that we don’t know enough about yet,” Snow says. “I think in a lot of cases, there’s no harm in it. It’s just that people can think of a lot of scary situations, and you don’t necessarily know if all the regulatory agencies and various checkpoints along the way are going to catch problems before they’re released.”
In 2002, Snow’s group crossed domestic sunflowers, that had an insect-resistance gene added, with their weedy relatives. The resulting hybrid plants did grow better, produce more seeds, and avoided damage from insects.
Snow points out that, even though some plants like sunflowers seem to be able to transfer certain genes easily and produce vigorous offspring that can continue to carry those genes, other plants and genes might not mix so well.
Snow is now looking at wild radishes, among other plants. She wants to know whether regular crops that haven’t been genetically modified can also make weeds weedier. Her results should contribute a better understanding about gene flow in general.
As genetically modified crops become ever more popular in countries around the world, concerns, too, have gone global. “Every country in the world is thinking: “Do we want these crops or don’t we? And is it safe here or not?’ And they want to know: If it was tested in the United States does that mean it’s safe in another country?,” Snow say. “There are a whole lot of questions people have about the safety of these crops, and I’m focusing on just the environmental effects.”
That’s enough to fuel research projects for years to come.
Excerpts from an Interview with Allison Snow:
– “Very little had been known about that maybe 10 years ago and that was when I started to get interested in these processes and these questions.”
– “That’s how we have to break it down and say: “I’m going to focus on this now and then the next step and then the next step.”
– “What we think is possible is that all the genetic diversity you get when a crop crosses with a weed could just provide some raw material for that weed to become more vigorous or more resistant to diseases”
– “We think it might be happening all the time, and no one’s really paid any attention to it before, and it would be good to know. It would be helpful just to know how quickly can weeds evolve, and are the ones that cross with the crops, are they evolving even faster than the ones that don’t have any crop relatives?”
– “I don’t like to talk about superweeds because I think it’s an exaggeration of reality. I think it’s misleading to tell people that just one gene or even three genes could make a really bad weed out of something that was just a harmless weed before that.”
– “I think they’re just different pieces of the puzzle, and I’m hoping that our results will give us a better baseline for understanding gene flow with and without the transgene.”
– “Every country in the world is thinking: “Do we want these crops or don’t we? And is it safe here or not?’ And they want to know: If it was tested in the United States does that mean it’s safe in another country? And so there are a whole lot of questions people have about the safety of these crops, and I’m focusing on just the environmental effects.”
– “We’re so proud of our little plots. I mean, we make sure they’re not going to hurt anyone else’s land. But we have these isolated gardens that are just full of weeds and to us that’s like as exciting as it gets, because we’re interested in the data that we’re going to get from them.”