Genetic modification may get a lot of consumers’ attention, but plant breeders have newer tools for creating crops. Food that’s been gene-edited using CRISPR is now on store shelves. In this episode, we look at biotechnologies such as gene-editing and CRISPR and how they could potentially help reduce food waste and create higher-yielding or disease-resistant crops. We’ll examine how these new techniques could produce a healthier potato and a longer-lasting tomato. And we’ll look at what biotechnology could mean for animal agriculture. We’ll talk to UC Davis experts working with these new tools and discuss what their work could mean for the future of food.
In this episode:
Diane Beckles, an associate professor, and associate postharvest biochemist. She is researching the molecular factors that lead to postharvest chilling injury in the tomato and other fruit.
Alison Van Eenennaam, extension specialist in animal biotechnology and genomics with the Department of Animal Science. She uses DNA-based biotechnologies in beef cattle production and agriculture systems.
AMY: Hey Alexa, this week we are going to be talking about the future of food.
ALEXA: Okay, just lay it out there. Don’t keep people in suspense or anything.
AMY: Yeah well that would be good radio. This is just a podcast.
ALEXA: And we’re going to discuss how new technologies can help us grow more food and waste less.
AMY: We’ll look at biotechnologies like genetic engineering, gene-editing and CRISPR and how they might help us feed more people worldwide.
ALEXA: These are really important topics but pretty tough to unfold.
AMY: Yeah, but let’s do it anyway.
(UNFOLD THEME MUSIC)
AMY: We’re going to start this podcast as we did the last one- talking about carrots.
ALEXA: Amy, what is it with you and carrots?
AMY: And we’re going to be talking to this woman.
DIANE: My name is Diane Beckles, I’m an associate professor in the Department of Plant Sciences.
AMY: Diane studies plant biochemistry. Or more specifically-
DIANE: In my lab we are interested in addressing basic questions about the factors that determine the quality of fruits and vegetables and cereals.
AMY: And even more specifically-
DIANE: How the quality of the foods we eat is affected by refrigeration.
AMY: So Alexa, ready for this?
AMY: Diane researches ways to prevent post-harvest chilling injury.
ALEXA: That’s cold.
AMY: Very. You ever put a tomato in a fridge?
AMY: How did it taste when you took it out?
Alexa: Kind of bland.
AMY: That’s how the tomato gets injured.
ALEXA: Poor tomato! Did I hurt its feelings?
AMY: Well, you ruined it. Still edible, but not so tasty. You might throw it away now, creating more food waste while some people go hungry.
ALEXA: Well that’s not cool. Wait, we’re talking about tomatoes, so why did you bring up carrots?
AMY: Because Diane’s interest in preventing post-harvest chilling injury, in a roundabout way, started with a carrot.
DIANE: It started when my dad gave me some carrot seeds to grow and I thought it was a complete miracle. To put these tiny seeds into the ground and then...
AMY: Boom! Food.
DIANE: And not just any kind of food but just this bright orange colored food that tasted really good and I knew was good for me.
AMY: How could that happen, was it…magic?
DIANE: It had to be magic, right? How could sunlight and dirt create this thing that had sugar and tasted good and was really pretty? I had a lot of questions and not many people could answer my questions. And so I realized over time that that's what scientists did.
AMY: What kinds of questions were you asking that people couldn’t tell you the answers to?
DIANE: Where did the carrot come from? My father told me something about photosynthesis and nutrients in the soil, but it didn't make sense. There were a lot of dots that he could not connect for me. But that started something in me. This desire to understand the natural world and especially plants. I just thought they were absolutely fascinating.
AMY: Her fascination with plants and fruits and vegetables started in Barbados, where she grew up.
ALEXA: And she grew carrots.
AMY: And Barbados is a small island.
DIANE: Barbados is gloriously 166 square miles.
ALEXA: That’s tiny. Really tiny.
DIANE: It’s just a speck on this earth and our population density is pretty high. We had, when I was a child, about 250,000 people on 166 square miles. And I worried tremendously about having enough dirt and enough soil to produce food for people on the island.
AMY: Which made her think about the even bigger problems like…
DIANE: How do we feed this growing global population given that our resources are limited?
AMY: Given Diane’s worry about feeding everyone, maybe you can guess what she believes to be one of the most important inventions in the last 100 years?
ALEXA: That would take me awhile, so… what is it?
AMY: The refrigerator. Why?
DIANE: It allowed us to store meat and perishable goods for a longer time and this was important to food security.
AMY: But the drawback of the refrigerator?
ALEXA: Post-harvest chilling injury.
DIANE: There are some fruits and vegetables that not only will you spoil the quality by putting them in the fridge, you can actually accelerate the rate at which they deteriorate. And we’re not talking about a small portion of what we eat we’re talking about at least 65 percent of the most consumed fruits and vegetables are affected when you put them in the fridge.
AMY: Produce like bananas, avocados, zucchini, pineapples, and tomatoes.
ALEXA: So if you put a tomato in the fridge for a while, then pull it out….
AMY: And instead of eating the bland tasting thing right away, you leave it out, itt would get even worse. You’d see dark spots and fungus. It would start to rot.
ALEXA: So Diane is trying to figure out a way to prevent that from happening.
DIANE: We are trying to understand the genes that are misregulated when this produce is stored at low temperatures. We believe that if you can understand how these genes are altered- you know you can start with developing biotechnological solutions but also storage solutions- maybe you can find sprays or dips or physical treatments to help make the produce a little more robust to preserve the integrity of these genes that are destroyed by refrigeration.
ALEXA: We went to Diane’s lab to speak with her PhD student, Karin Albornoz, who is working on the problem.
AMY: Karin is conducting research on the genes of the tomato. She has in front of her a small Tupperware-looking container of tomatoes.
KARIN: What we did in the lab was create transgenic tomatoes that have a gene- I’m putting my gloves on- and these tomatoes have a gene from another species.
AMY: Yes, foreign DNA from another species. It’s genetic engineering or what consumers sometimes call a GMO. If you need a refresher on that, please listen to Episode 2 of Unfold.
ALEXA: But in this cold tomato case, Karin has introduced a gene from a wild species of tomatoes that evolved in the Andes to tolerate cold and…
KARIN: And also from a weed that doesn’t enjoy cold but is more cold-tolerant. So the tomatoes I’m evaluating now were in the cold room at very low temperature for three weeks and then they were transferred to room temperature for three days.
ALEXA: The result was unexpected and … well … not good.
KARIN: These tomatoes don’t look very good they have srt of a yellowish, orangish color and they have signs of decay. There are fungi growing on the tomatoes right now because they are damaged by the cold treatment. And that is an interesting result because we try to understand what is happening behind these results and see the real effect of the gene we introduced into the tomatoes.
AMY: Finding solutions that would prevent the tomato from rotting and improve handling after it’s been picked would help prevent food waste.
ALEXA: But Diane says we’re obviously not there yet.
DIANE: In terms of coming up with a lasting solution that would make a huge shift in industry I think that may be at least 10 years away if not beyond. I hope I am wrong. I would love to be wrong.
AMY: It’s even more critical to address these issues as the climate changes and the population is predicted to boom.
ALEXA: Which is why Diane isn’t just hoping to improve the shelf life and handling of the tomato but also another more widely eaten vegetable– the potato.
DIANE: Potatoes, tomatoes, potatoes, I feel like there should be a song about them. It’s my life. Ketchup and chips, anyhow.
ALEXA: So what’s wrong with potatoes you might ask? After all, you can store them for a pretty long time.
AMY: But like the tomato, it’s also sensitive to cold. So instead they’re stored at higher temperatures than ideal. That can break down the starch to sugar.
DIANE: So what happens when the starch is broken down to sugars? Well, you lose some of the yield, right, because the sugars- and this is not the stuff that we value in chips and fries.
AMY: But something even more insidious happens. Especially if you then throw those potatoes in hot oil.
ALEXA: You mean make French Fries?
AMY: Or chips if you’re from Barbados.
DIANE: So when you fry your chips and you see those black spots or if you go to a fast food restaurant or you buy frozen chips and you see blackened regions that’s probably attributable to acrylamide formation.
AMY: Acrylamide is not good.
DIANE: It’s a carcinogen.
AMY: Now we could all just avoid fries.
ALEXA: But what would be the fun in that?
Amy: So Diane wants to make these fries "CRISPR-ed.
AMY: Trying to come up with a verb for a process that’s hard to explain.
ALEXA: Ok, well that didn’t work.
AMY: She wants to use a gene-editing technology called CRISPR.
ALEXA: And CRISPR stands for-
AMY: Which you really don’t need to commit to memory.
ALEXA: All you need to know is that this DNA editing tool...
AMY: Could revolutionize food. Think of it as a new kind of molecular scissors. You can introduce or eliminate certain traits without requiring foreign DNA or genes from another species, which you do with GMOs.
DIANE: There is a precision there that is absolutely delicious.
AMY: Delicious. She really said that.
Diane: You hardly have a genetic footprint on the edited crop. It’s so precise and so similar to the original parent that you’ve modified that the USDA has said that edited plants do not need to be treated as regulated articles. They are essentially non-GMO.
ALEXA: Diane is using this CRISPR technology to change the starch in the potato.
DIANE: We want to alter the structure of starch in potatoes not only so that it’s difficult to break down during cold storage, which would help with the acrylamide problem, but also so it’s difficult to break down when we eat it.
AMY: Making the starch more fibrous and well, healthier.
ALEXA: It sounds like a three for one right?
AMY: Right. She’d create a healthier potato, with a longer shelf life that doesn’t produce acrylamide, which is carcinogenic.
DIANE: I have this vision that if you could use gene-editing technology to produce a food product that clearly the consumer can see would have positive benefits for their health and this product would also help mitigate environmental damage- that they would gravitate toward such a product, they would see the value of biotechnology.
AMY: Diane believes CRISPR and gene-editing wouldn’t just create healthier potatoes or food that won’t spoil. It could also create crops that could withstand droughts, floods and disease.
ALEXA: All of which are imperative with climate change and a growing population. But use of biotechnology isn’t an easy sell as we’ve seen with the GMO debate.
AMY: While the USDA doesn’t regulate gene-editing in plants as it does in GMOs, there are still concerns about using gene-editing and CRISPR technology when it comes to breeding animals. Alexa, I’m sure you’ve heard about our hornless cows that animal geneticist Allison Van Eenennaam has bred.
ALEXA: Yeah, she used gene-editing to prevent a cow’s offspring from having horns.
AMY: Right, and this was for animal welfare reasons to prevent them from hurting each other and their handlers. Right now, farmers burn off a calf’s horns.
AMY: Yeah, exactly. So I went to our feedlot here on campus to check up on them and talk to Alison about the future of gene-edited animals.
ALISON: Hello guys…They’re very chatty this morning, how are you boys?
AMY: Alison is talking to her hornless cows and well, they’re talking back
ALISON: What do you think about not having horns? Wow didn’t know they were that vocal.
AMY: Instead of horns typical of the breed, these guys have hair where horns should be. Alison used gene-editing to knock out the gene responsible for horn growth and replace it with a gene from a bull that doesn’t produce that trait. Some cattle breeds, like Angus, naturally don’t grow horns.
ALISON: There’s about 9 million dairy cows in the U.S., so that’s about 9 million calves a year or so that are having their horns burned off. And so, I know I’m a geneticist but genetics is a better way to address this problem than physically burning them off, so that’s the idea.
AMY: Now Alison is researching any potential effects from the gene-edit.
ALISON: We’re being asked, are these animals, you know, normal? And so it’s like well, yeah, they’re cows and they don’t have horns. And so we’re also documenting their health status and their- eventually milk production- and whether the meat in the case of the bulls – sorry boys- is different to normal because it’s the first offspring of an edited animal we’re doing this kind of really thorough evaluation of everything.
AMY: Luckily for Alison, today is the day the gene-edited female offspring gets a pregnancy check. A pregnancy is important in determining whether a gene-edit affects milk.
ALISON: Are you going to preg check her? Ooh, oooh, we should go do that. Let’s go do that. It’s very lucky that we’re out here for this.”
AMY: If you’ve ever seen a cow get a pregnancy check, you know why it would be hard to imagine anyone getting excited by it. But hey, I’m no animal scientist. Veterinarians soon corral the animal into a squeeze shoot that steadies her for the pregnancy check.
VETERINARIAN: So I’m going to put my probe in...
AMY: But today the vet had to deliver bad news.
VETERINARIAN: Right now I’m not seeing any evidence of pregnancy.
AMY: Alison was hoping the gene-edited animal, named Princess, and her control in this experiment, a non-gene-edited cow, were both pregnant at the same time in order to test similar milk samples.
AMY: Alison’s other gene-editing project is using CRISPR to create bulls that will father only male offspring.
ALISON: Males are about 15 percent more efficient than females at converting feed into gain so they basically require less feed to get to market weight.
AMY: That could make the beef industry more efficient. In fact, gene-editing technology holds huge potential in farm animals. It could make pigs, chickens and cattle resistant to viruses and nasty diseases. But unlike gene-editing in plants, the U.S. Food and Drug Administration says it will treat the edited DNA of an animal as if it were a drug.
ALISON: It’s really made gene-editing as if we’re doing drug research like we’re testing pharmaceutical product on them or something and it’s not. It’s their DNA has been tweaked, it’s not a chemical.
AMY: The concern in part, is that gene-editing technologies like CRISPR may have so-called off-target effects. Altering the DNA in one part of the genome may have consequences on another part. But Alison says a lot of the controversy stems from the potential use of CRISPR to genetically engineer humans.
ALISON: That’s fine. So a really simple way to address that would be to say if you’re editing humans then you’re subject to this regulation, but if you’re doing cattle breeding or food animal alterations where you’re not introducing foreign DNA, in other words, you’re not making it a GMO, then you’re going to be treated like traditional breeding.
AMY: She says the FDA rules for animals are a huge regulatory block that will require elaborate and costly safety studies. She believes it could end gene-editing research on animals in the US.
ALISON: It concerns me that plant breeders will be able to use this technology and animal breeders won’t. At the end of the day we’re both producing food and in fact, I would argue the demands for things like disease resistance and some of the animal welfare traits like not growing horns that could be addressed using these genetic approaches, will basically not be allowed to be used.
AMY: So Alexa, Alison says gene-editing can be used as one of the main drivers of sustainability. If we can use it to produce cows resistant to infection, chickens immune to avian flu, we could keep production high.
ALEXA: And reduce the use of antibiotics, which could be healthier for humans too.
AMY: Making a gene-edited product that has positive attributes for humans seems to be an easier sell. So it kind of makes sense that the first gene-edited crop, which just hit the U.S. market this year, is a gene-edited soybean that is supposed to be healthier for consumers.
ALEXA: That’s right, I heard about that. It apparently creates an oil with no trans-fat and is being served up in some restaurants. But regulations seem to be putting a hold on using the technology in animals.
AMY: Yeah, and in Europe, gene-edited animals and plants are being regulated as GMO foods. So it’s even tougher to bring either one of those to the marketplace.
ALEXA: So I guess we’ll just have to wait and see how all of this unfolds.
AMY: Such an appropriate verb, Alexa. Next time on Unfold, we’re going to talk about the Internet of Food, whatever that is. We’ll explain it.