In five years, there might be a little CRISPR-edited corn in your breakfast cereal or CRISPR-edited wheat in your pasta. CRISPR’d tomatoes and CRISPR’d pork might follow. There’s already a little CRISPR in your yogurt.
It’s not hyperbolic to say that CRISPR-Cas9—new technology that makes it possible to quickly and easily edit DNA—is changing the future of food. The method could eventually be used to tweak almost anything we eat, selecting traits that can make agriculture more environmentally sustainable and productive, or the resulting food healthier.
The technology is based on a natural process. Many bacteria have a hidden talent: In order to protect themselves from viruses, they cut the virus’s DNA. First, they save a fragment of an invading virus’s DNA in a pattern known as CRISPR (short for “clustered regularly interspaced short palindromic repeats,” which describes how the segment looks). If the virus comes back, the bacteria can recognize and hone in on it. Then it uses an enzyme called Cas9 to make a cut in the DNA, disabling the virus.
A few years ago, researchers figured out how to use the same method to edit any kind of DNA. By using guide RNA—the same type of molecule that bacteria use to find and fight a virus, but that can also easily be made in the lab from DNA in a few steps—scientists realized that they could target any spot in the genome of a plant or animal and make a deletion or paste something else in.
“I think a good analogy is a molecular scalpel,” says Jennifer Doudna, the University of California-Berkeley professor who was first to publish a paper about using CRISPR for gene editing in 2012 (Doudna and her colleagues are currently embroiled in a bitter legal battle with MIT researchers over the patent for the technology). “It’s a way that scientists can make very precise changes in the DNA and cells of organisms—down to the level of a single letter in the DNA code out of 3 billion base pairs in the human genome.”
If editing a single gene might have taken weeks, months, or even years with older techniques, now it can happen in a matter of days with a single grad student. Old techniques—such as using a “gene gun” to shoot DNA into plant cells to make something like the earliest GMO soybeans—took far longer to reach a desired result; researchers would have to grow plants to see which ones happened to end up with the traits they wanted. More recent gene-editing tools, such as TALENs and zinc fingers, made it possible to directly target a particular gene for the first time but are more time-consuming than CRISPR in their design and construction.
CRISPR is comparatively easy, because all it requires is ordering some products that are widely available and synthesizing RNA, a simple process in a lab. “This is what I call the democratization of gene editing,” says Rodolphe Barrangou, one of the first researchers to realize how bacteria were naturally using CRISPR. “There were gene-editing technologies that existed before . . . but it was difficult, it was expensive, it was time-consuming, it wasn’t trivial. What CRISPR really has done is enable that gene-editing revolution that we’re witnessing.”
Since the beginning of last year, researchers have published more than 16,000 studies using CRISPR: editing mouse genes to repair genetic disease, designing better biofuels, figuring out which genes are responsible for certain traits and illnesses, and even—controversially—genetically editing human embryos.
But put the deep moral quandaries about human gene editing aside for a minute. In the world of farming, researchers are using CRISPR to work on some foods that might have been too complicated or expensive to genetically engineer in the past, along with the bigger crops that already have GMO versions.
At DuPont, researchers are working on CRISPR/Cas9-edited versions of commodity crops such as corn, soybeans, canola, rice, and wheat, which they expect to have on the market in 5 to 10 years. The plants have new traits like drought resistance and higher yields—both critical features for farmers trying to deal with a changing climate and the fact that the world population is growing faster than our food supply.
“When you think about the fact that your average biotech crop takes 10 to 17 years, that’s a really remarkable speed compared to where the market is today,” says Rachel Haurwitz, cofounder of Berkeley-based Caribou Biosciences, which partnered with DuPont to provide Caribou’s version of CRISPR. “I find that really, really exciting.”
The technique can also be used to remove allergens in peanuts, or make food more nutritious, all while using genes that naturally occur in the plant.
It might also save the modern banana. The Cavendish banana, the only type of banana sold in most grocery stores—because it is grown around the world as a monoculture crop—is on the verge of extinction because of a fungal disease. While some researchers are racing to test less-common varieties of bananas to try to find an alternative, a Korean researcher hopes to use CRISPR to snip out the receptor that the fungus uses, so it would no longer have an effect.
CRISPR may also keep livestock healthier without relying on antibiotics, which are overused in animals and leading to antibiotic resistance that is killing humans. “You can actually harness CRISPR systems as antimicrobials, and they provide a great alternative to classic antibiotics,” says Barrangou. “You can program them to selectively target one or more organisms of interest. Whereas most classical antibiotics are very broad-spectrum—when you consume them they wipe out the good guys and the bad guys indiscriminately—CRISPR is opening new doors for programmable antibiotics whereby you could selectively eradicate a pathogenic species.”
Some researchers are also experimenting with directly editing livestock genes to help protect animals from disease. One pig disease costs farmers $600 million a year; in 2015, researchers created a gene-edited version of pigs that couldn’t catch the illness. Twenty percent of all animals raised for food are lost to disease, which is a massive sustainability problem as well as a cause of animal suffering. Gene editing could potentially help change that in a way that traditional breeding hasn’t been able to.
Other meat might be gene edited to be healthier. The same Korean researchers working on the Cavendish banana have also created a variety of pig that is extra-muscly, so it can produce leaner cuts of pork. “We could do this through breeding,” lead researcher Jin-Soo Kim, of Seoul National University, told Nature. “But then it would take decades.”
CRISPR can also be used in its natural form—and it already is. When Barrangou first began studying CRISPR in bacteria, he realized that it could be harnessed to help prevent food waste in dairy products such as cheese and yogurt. It’s not uncommon in the dairy industry for viruses to attack the cultures that are used for fermentation, and that can lead to the loss of thousands or even millions of gallons of milk in a single instance. By selecting variants of the cultures that naturally get vaccinated against viruses, the industry can prevent that from happening.
“If people eat yogurt and people eat cheese, there’s a 50% chance, give or take, that people have been consuming dairy products that were manufactured using CRISPR-enhanced bacteria,” he says. The industry has used the natural form of CRISPR for more than a decade. It can also be used in other fermentation processes, such as pickling or making kimchi, soy sauce, or wine.
There’s potential for CRISPR to be used much more widely. But it isn’t clear yet if the technology can avoid the Monsanto problem—the public distaste for eating anything genetically edited. Public support for GMO food is still very low, despite the fact that the majority of scientists believe it’s safe. In a 2015 survey, most Americans said that genetically engineered food should be labeled—and that they probably wouldn’t buy it. More than half of those surveyed said they think it’s unsafe.
It’s possible CRISPR-edited food might not be seen the same way. In some cases—when the technology is simply used to delete a gene in a plant, rather than adding in anything from another species—the USDA doesn’t consider CRISPR’d food a GMO. The plant looks genetically identical to something that could have been created through cross-breeding or evolution.
Even adding a gene could sometimes end up being the same as a traditionally bred crop. “I think it’s exciting to think, for example, about some of the gene variants that are known to exist in wild strains of particular crops of interest, and the ability to use CRISPR to insert those naturally occurring wild variants into elite crops in a very rapid way, in a very precise way,” says Haurwitz. “It gets you the same product as if you had spent years and years breeding the wild strain with your commercial strain. At the end of the day, it’s the very same product, but it could get to consumers substantially faster by using CRISPR.”
Cibus, a San Diego-based startup making CRISPR-edited flax, position their products as a non-GMO food. “DNA ‘spelling changes’ occur naturally in all plants and are the basis behind the diversity we see in plants as we walk in our local parks or in the forest,” says Greg Gocal, senior vice president of research and development at Cibus. “During domestication events that selected the world’s crop plants, genetic diversity was lost. Breeders have been working for decades to augment crop diversity using mutation breeding. However, this is random. . . . Non-transgenic breeding, which includes technologies such as precision gene editing, can also restore lost genetic diversity.”
Even in Europe, where regulation has been stricter, there are early indications that CRISPR’d foods may not be regulated. In Sweden, authorities recently said that CRISPR-edited plants (as long as they don’t contain foreign DNA) shouldn’t be defined as GMOs under EU legislation.
EU law says that it must be possible to detect a GMO food—and because CRISPR-edited foods are identical to those that are not GMOs, they can’t be detected. It also says that the changes that occur must not be more “uncertain” than something that could occur with techniques like breeding. “The changes are identical to those that could occur with techniques that are not considered to produce GMOs,” says Stefan Jansson, head of the department of plant physiology at Umeå University.
While the Swedish ruling could be overturned by the EU Commission, Jansson believes there’s increasing support for biotech food. “It is clear that there are very many, in addition to us in the scientific community, who are deeply concerned that the lack of access to efficient plant breeding is a serious threat to the possibilities to make food production sustainable,” he says. “Since most politicians consider it to be political suicide to express their opinions about GMOs, maybe they now dare to stand up.”
In an analysis of the psychology behind why people dislike GMOs, researchers pointed to transgenesis—the mixing of species—as one problem. People tend to see inserting a fish gene into a tomato as fundamentally unnatural. But if CRISPR is used to insert genes from the same plant (or just to take a gene away), it’s possible that might shift attitudes.
It’s also possible that it won’t. “Given the fact that CRISPR can be viewed as tampering with a organism’s essence, I’m afraid that biotechnologists might face an opposition similar to the GMO case,” says Stefaan Blancke, co-author of the paper on the psychology of GMO opposition.
“There probably are some critics who are going to be more accepting because of CRISPR,” says Paul Thompson, a bioethicist and professor at Michigan State University. “But the vast majority are focused on broader philosophical issues. . . . You’ve got this community of critics who in some respects don’t really care that much about what the details are. There’s been this kind of creation of a lot of—I don’t want to be dismissive, but I’ll use the word mythology—about GMOs. And I’m constantly talking to people that I like and respect in the sustainable agriculture community who are just quite, at least from my perspective, misinformed about what GMOs actually are and what they actually do.”
One of the few scientists to speak out about GMOs argues that CRISPR is fundamentally no different than earlier technology, and that CRISPR-edited foods should be regulated before they go on the market. “Is it more exact than the use of a gene gun, where it’s literally scattershot? Sure,” says Michael Hansen, senior staff scientist at Consumers Union, the organization that publishes Consumer Reports. “It’s more exact, but there can still be off-target effects.”
Hansen points to the fact that Doudna and other researchers have called for caution in the use of CRISPR in humans—because of potential unknowns—and thinks that the same caution should be applied to food. “We’ve never been against the use of any technology,” he says. “We just think that before these technologies come out on the market—whether it’s CRISPR or anything else—there should be required safety assessments, and those crops should be labeled.”
For now, however, the technology is moving ahead, and most researchers think that’s a good thing. “I think there’s real potential from a technology perspective,” says Haurwitz. “But I think that potential can only be realized if we the industry do a good job of communicating to the rest of the world how beneficial it will be for growers, for consumers . . . for everyone involved in the food value chain.”