Recently, I talked to Kate Scheibel, a second year Ph.D. student in plant biology at UC Berkeley, about GMOs and her personal experiences with genetic engineering.
You’ve said you do a lot of work with plant pathology. What does that mean?
Plants, like animals, have pathogens that will infect them. Each cell is responsible for recognizing when it’s being invaded by pathogens.
I mostly work at a cellular level: imagine a receptor with a circle shaped hole that sticks outside of the plant’s cell into the extra cellular space. A pathogen will either excrete molecules, or it’ll have things sticking out on its surface that are circle shaped, that are recognized by the plant. Then, once that recognition happens, the plant sends a signal into the cell and changes its biology to make it so the pathogen can’t survive. This causes what we call a molecular arms race: the pathogen obviously doesn’t want to be recognized, and the plant wants to continue to recognize the pathogen.
One of the things that is largely true about plant pathology is in the past, we’ve bred plants that have those receptors or analogous systems that are easily overcome. Then, because of the way that traditional breeding works, that single trait can be picked up from the wild or picked up from random variation, and bred into a crop plant. But if the pathogen can no longer infect the plants that have been bred to have that [resistance] trait, it’s under tremendous pressure, so evolution happens and [that pathogen] isn’t recognized anymore. What I personally work on is looking for more durable resistance, which is kind of asking the question “Why can’t all plants be infected by all pathogens?”
For instance, a cabbage is never infected by a certain potato pathogen. We don’t know how the plant prevents that, so that’s what I’m working to figure out.
So you’re searching for why things don’t get infected?
Yes. I work on a pathogen, blumeria, which normally infects barley. It’s very good at infecting barley. A related pathogen, golovinomyces, is able to infect this mustard weed called thale cress, which I also work on. Blumeria just can’t infect thale cress, but that related pathogen can.
We look at attempts of that nonadapted pathogen to infect thale cress to try and figure out what genes are responsible for that incompatible interaction. The idea is that if you took those genes out the plant, then you would be able to get infection from that barley pathogen. Obviously, the end goal of this is not to create susceptible plants, but to be able to put that resistance into a naturally susceptible plant.
So you’ll cut and paste that area of the DNA sequence into a different plant?
Right. If we can figure out what the associated genes are, which is not necessarily easy.
This is probably an obvious question, but does what you’re doing fall under the umbrella of genetic modification?
Yes, I use genetic engineering techniques in my work constantly because it’s so much faster than traditional breeding. It would take me a really long time to find a particular trait in the wild and then introduce it into my system. This way I’m able to find a gene, and either put it in or take it out of the system within one or two generations, which translates to three to six months instead of a full year.
Is it a specific plant you’re trying to “help”? Or are you trying to apply what you’re doing to as many plants as possible?
My research is more basic–we’re just trying to understand the general pathway. The idea is that that it can be applied to whatever system that it’s relevant for, and we don’t know how relevant it is. We work with thale cress because it’s a small organism. It grows really quickly, it has a really short generation time–going from planting the seed to getting the next generation of seeds proceeds very quickly.
Explain it to a five year old: what’s the definition of a GMO?
A genetically modified organism is an organism that has a gene or genes in it, the origin of which is not the species that they are. You can do genetic modification within the same species–there’s no reason why you can’t do it–but generally, what people are talking about when they’re talking about GMOS are genes from other species being put into some crop plant.
The genes can be from anywhere. It doesn’t matter if it comes from a bacteria or a plant or an animal. They all use the same genetic code, which is really awesome. You can put a gene from anywhere–any kingdom of life–into a plant if you want to. The origin doesn’t really matter.
So we shouldn’t be freaked out if our tomato has genes from all over the place?
Right. There’s nothing inherent to that gene that makes it a tomato gene, aside from the fact that it’s found in a tomato. You wouldn’t be able to tell the difference if you looked at a sequence file from a tomato and from a human being. They’re really similar, it’s just ATGC in different permutations.
Do you have any qualms with transferring genes from one plant to another, extremely dissimilar plant?
In terms of just putting genes into things, I don’t have a problem with it. One funny thing that people say is “You’re transferring genes from one organism to another, that wouldn’t necessarily happen in nature,” but there’s a lot of gene transfer going on in nature. You’ve seen things that look like big tumors on trees? What’s happening is bacteria is infecting the plant, it’s injecting its own DNA into the plant and changing the plant’s DNA to produce the nutrients that the bacterium can use.
These cells are producing a ton of food for the bacteria, and it makes this great little house for the bacteria to live in. This plant is expressing bacterial genes. It happens in nature, and then we use that system in plant biology because it’s convenient. You can replace those tumor genes with whatever you want, put them into the bacteria, then the bacteria will put them into a plant for you.
It’ll do your work for you.
Yes. That’s one way to make GMOs. It doesn’t work in all systems, but that’s how I make my plants do things that they normally wouldn’t. Things get transferred between kingdoms that can’t breed with each other. Saying “Oh, this is bad because it’s unnatural,” is wrong both that agriculture itself is unnatural, and also, it happens anyway. We might as well make it happen in a way that’s useful for us.
There are some moral issues in terms of what you’re putting into the genetically modified organisms but I think it’s unfortunate that that’s being conflated with the technology. It’s like saying that steel manufacturing is inherently immoral because you can make guns out of it. Ok, but you can also make trains or other useful things. (Read more.)
What are some of those moral issues about what you’re putting into the plants?
One thing is hybrid corn. Seed companies will sell corn that’s a cross between two different parent varieties. It has half of one genome and half of another genome. Because of the way genetics work, that corn is really, really good. It grows tall and uniformly, but if you breed it to itself, and then grow it the next generation–if you save your seeds–the corn you get is pretty crappy.
That’s because of the way that genetics works, and the way that segregation works. But since people figured out this was the case, any company that sells that F-1 corn or that hybrid corn, knows that you are going to have to keep buying your seed from them every year. The commodification of life is not a new problem. But it’s been brought to the forefront by this kind of technology.
Then there’s potentially creating monopolies on things. This is not a new problem, [but Monsanto] sells this Roundup Ready corn that is resistant to an herbicide sold by the same company. Instead of using the technology to make a plant that’s resistant to a pathogen, or a plant that can grow better in certain conditions, they make a plant that can survive this herbicide that kills everything–except for the plant. And that’s one of the reasons that people say “Oh, GMOs are bad for the environment”
GM crops are not bad for the environment. But certain applications of the technology can be bad for the environment. But I really don’t believe that there’s anything inherent to genetically modified foods that is damaging to the environment or that’s unhealthy. It’s just a technology and it can be used in ways that aren’t great.
I understand where people will vilify some of these big agricultural companies–but you have to understand, it’s difficult to figure out what gene you should put into a crop to make it better. These biochemical pathways are pretty complicated, and we don’t really understand them. It’s really expensive and time consuming to figure this out. And these companies want to make a profit, as every company does.
What’s the process like when you’ve identified a problem, something like citrus greening, that you want to change. Do you just start throwing genes into a plant and see what works?
Generally, no. One of the big bottlenecks with making GMOs is that we doesn’t necessarily know the process by which things happen in cells. It’s rarely only one gene that’s important. You aren’t just throwing random bits of sequence into an organism and seeing what happens at the crop level. Generally, first you have some problem in agriculture, greening in your citrus. First you would figure out how resistance happens…
Which is what you’re working on right now.
Exactly. Let’s say I identify one gene. You figure out one gene that‘s responsible for resistance–say you found it in a lemon. Basically, without getting too technical, you cut [the gene] out of the lemon. You take it out of the lemon and you coat a little gold bead with pieces of that DNA and you shoot it into the plant. They do this with something called a gene gun and it literally shoots tiny gold particles covered with DNA into the plant.
And for some reason–as far as I know, people are not sure of exactly why–the plant will incorporate this DNA into its genome. Then you can regenerate plants from that tissue, grow them up and breed them a bunch of times with themselves to make sure you have all of the traits you want in the original–you want it to be juicy, and you want it to flower at a certain time. Then you grow up this orange variety that now has the citrus greening resistance in it. It’s exactly the same as it was before, plus this one trait.
How does this compare to traditional breeding?
We’ve had genetically modified foods forever. If genetic modification means changing the genetics of something to make it more like what we want, that’s what agriculture is. The precursor of corn is called teosinte and it has about six kernels. Though selective breeding, we’ve made it have these huge ears. We’ve bred it because we want to eat it, and we want it to be efficient and productive.
Neither of these [options] are natural. You are selecting for traits, nature is not selecting for traits. The thing that’s kind of funny about people’s perceptions of genetically modified foods is that this “natural” method of breeding, which has been used since agriculture began, is really not that natural. (Read more.)
What do you think of GMO labeling?
I think consumer choice is important. I have no problem with that, [but] I have a couple of issues. First of all, USDA certified organic products cannot contain genetically modified anything. It’s one of the stipulations of getting that certification, so if you really don’t want to have GMOs in your food, you can buy things that are organic.
The other thing is that mandating the labeling of a product, at least right now, is generally because things are unsafe. Things that require labels on them are cigarettes and alcohol, which have demonstrated negative health effects. Whereas there’s no demonstrated–legitimately demonstrated–health effects of consuming genetically modified foods. You probably would have a problem if you ate the first generation of a genetically modified crop, because that was probably exposed to a whole bunch of antibiotics to select for the genetic modification. But the argument that the resultant generation’s food is unsafe doesn’t make any sense. They haven’t been exposed to the same environment, they are no different from any other crop. They have a DNA sequence in them and they make a protein that whatever crop it is wouldn’t normally make, but that doesn’t make it inherently unsafe.
You could genetically engineer a toxin into a plant, and that would make it unsafe, but there’s nothing inherent to the technology that makes food unsafe. So I don’t think that mandating a label is a good thing, because it’s playing to this erroneous connection that people make between genetically modified foods and things that are unsafe.
You work at Berkeley’s Energy Biosciences Institute, which is partially funded by BP. Monsanto funds a lot of work at places like UC Davis—how does this not create a conflict of interest?
Being funded by someone doesn’t mean that you work for them. To be funded by someone, you give them a proposal and they say “I like what you’re doing and I’d like to fund it.” If they influenced the outcome of your results–like not reporting something because it might damage them in a financial way–that’s unethical. It’s really unethical to allow the sources of your funding, whether it’s from the government or from a private company, to influence the reported results of your work. I don’t know any scientist who is that unethical.
Everyone has to be funded. Research is really expensive. And where you’re getting your funding from is always going to influence what source of work you’re doing. The NSF (National Science Foundation) publishes goals, and seeks proposals for projects aimed at solving certain things. If you propose a project aimed at a certain thing that the NSF wants you to do, that’s changing your research aims to get funding. It’s not really any different where the money’s coming from. We still publish in peer reviewed journals, we still go to the academic conferences, all faculty members are faculty members of the university, and it’s just that the money happens to come from BP rather than the NSF or NIH.
You talked about how GMOs can help with the issue of nitrogen depletion…
Potentially. If you grow corn on the same field for a long time, eventually that soil will be kind of shitty because it doesn’t have any nitrogen left. If you can make corn fix nitrogen so it doesn’t take all of the nitrogen out of the soil, then that would solve a big problem.
But isn’t that a natural barrier to keep from monocultures from forming? With any of the problems you’re “fixing,” are they there for a reason? Or is that just my Luddite thinking from too many Michael Pollan books?
I don’t think monoculture is a good idea, from the perspective of diseases and from the perspective of the loss in variation of what we eat.
I think that variety is really important and I think we should preserve it because we don’t make these genes from scratch. We don’t just say “Oh, I would like a resistance protein to citrus greening.” We can’t just write that. We have to find it somewhere and move it. So I think natural variation is really, important and it should be preserved, but everything doesn’t have to be the same that it is now.
This [technology] might allow for lots of different kinds of apples to be grown without some of the problems. Say you have a really cool variety of apple but unfortunately it needs a lot of water. Potentially, you can genetically modify that apple so you can keep growing it without as much water and then you don’t lose that variety.
That’s one way you can use this technology. Everyone who’s advocating for cultural acceptance of genetically modified foods isn’t advocating for Big Ag monocultures. It’s an unfortunate dichotomy–partially it’s because only Big Ag who can afford to make these crops at this point. But as we’re getting a much better understanding of how plants work and of how genes and proteins on a very small level are working, I think that there’s going to be lot more things that we could do with GMOs. I just hope that they aren’t so vilified in the public opinion that no one’s willing to do them. (Read more.)
Where do you see GMOs going during the span of your career?
I don’t think that scientists are going to stop using these genetic engineering techniques to figure out answers for things. Most people don’t know how agriculture works, because we’re really far removed from our food source. Which may or may not be a problem—I think it allows us to specialize in other things and live in cities and that’s great—but if you don’t know how agriculture works and you don’t know what it means for them to be genetically modified, I think a lot of people are susceptible to this untrue idea that GMOs are unsafe or damaging to the environment and it’s a real shame.
People talk about, what if we make a food that has a vaccine in it? When you eat it, you get vaccinated. That eliminates the problem of dirty needles or distribution of medical supplies or trained people who can distribute this stuff. If you could give someone an apple and then they’re vaccinated against tuberculosis, that is potentially really awesome. It’s far away but there’s no reason that it’s not a potential thing we could do.
When you’re talking about GMOs, they seem so innocuous. Why do you think there’s so much vitriol around this topic?
It makes sense. You hear people talking about Frankenfoods, or those cartoons with the eyes on the corn–that’s terrifying.
One gene encodes one protein, right? And if you put in one gene, or ten genes, or 20 genes into a crop all you’re putting in is the ability for that crop to make those proteins. They’re just proteins, and they’re doing some function inside the plant that could potentially be great.
People are afraid of change. The planet is able to support us right now, and maybe if things change it won’t be able to support us anymore. That’s a real fear. But the example of a mosquito comes to mind. Mosquitos exist and I don’t like them, I wouldn’t mind if they didn’t exist anymore. Maybe they exist for a reason–they have a niche in the environment, things eat them and they exist in the ecosystem–but they also vector disease. I would rather have a change in the ecosystem, who knows exactly how far reaching it would be, and save the lives of thousands or millions of people who are dying from malaria or West Nile than to just keep things as they are because that’s how they are. Natural variation is important and it should be preserved, but everything doesn’t have to be the same as it is now.
Do you have a favorite GMO?
I think golden rice is a really good idea. The idea behind golden rice was to produce the precursor to Vitamin A in the rice grain, which they got from a daffodil because it produced a lot of it. There are people with pretty significant Vitamin A deficiencies, and if they eat this golden rice, then it could solve a big problem pretty easily.
Part of the problem with golden rice was that it wasn’t bioavailable. If you ate golden rice, it kind of moved through you too fast to get at the Vitamin A in it. I think people got a little excited about it before it was totally tested and then it was seen as a flop, but that’s a really great idea! That’s the ideal iteration of genetically modified crops, using it to solve targeted problems without disrupting an entire system. It’s such an elegant solution to a problem.
Kate Scheibel grew up in Fabius, NY and did her undergrad at Cornell. She moved out to Berkeley to attend grad school in the Plant and Microbial Biology department at UCB in 2012 and joined Shauna Somerville‘s lab.
Shelby Pope lives in Oakland. Her favorite GMO is a DiGiorno stuffed crust pizza.