Jennifer Doudna, one of the inventors of the revolutionary gene-editing tool CRISPR, says this technology will help the world address the growing risks of climate change by enabling the creation of plants and animals better adapted to conditions of intense heat, severe drought, high humidity or climate instability.
“The potential is enormous,” says Doudna, who shared the 2020 Nobel Prize in Chemistry for his role in the discovery. “A revolution is happening now with CRISPR.”
Last month, the Innovation Genomics Institute (IGI), founded by Doudna, hosted the Climate & Agriculture Summit at the University of California, Berkeley. At the event, speakers highlighted the role of gene editing in mitigating the growing dangers of climate change. Doudna gave a brief interview to MIT Technology Review during the event, which was closed to the public.
She and her co-authors published their landmark paper on the technique in the journal Science 12 years ago, demonstrating that a bacterial immune system could be programmed to locate and remove specific sections of DNA. Recently, the first patients began receiving approved medical treatment with these “genomic scissors” — a gene therapy for sickle cell anemia. Additionally, a growing list of foods created with CRISPR are gradually arriving on supermarket shelves.
Many more CRISPR-edited plants and animals are on the way, and some have been altered to promote traits that help them survive in conditions driven by climate change, beginning to fulfill a long-standing promise of genetic engineering. This includes the breeding of two lines of cattle by the Minnesota company Acceligen that have been edited to have shorter coats, ideal for warmer climates. In 2022, the US Food and Drug Administration (FDA) determined that meat and other products derived from these animals “pose low risk to people, animals, the food supply, and the environment” and can be marketed to American consumers .
Other companies are using CRISPR to develop corn with shorter, tougher stalks, reducing crop loss during more intense storms; new cover crops that can help sequester more carbon dioxide and produce biofuels; and animals that could resist zoonotic diseases that climate change may be helping to spread, including bird flu.
The IGI, for its part, is working on developing rice that can withstand drier conditions, as well as crops that can absorb and store more carbon dioxide, the main greenhouse gas driving climate change.
Older genetic modification techniques, which involve transferring genes from one organism to another, have already generated major agricultural innovations, including herbicide-resistant crops and corn, potatoes and soybeans with enhanced protection against pests. The use of these tools to alter cultures has sparked fears that so-called “Frankenfoods” aggravate allergies and cause illness in humans, although these health concerns have been largely exaggerated.
The big hope is that CRISPR’s ability to remove specific parts of DNA within the existing genomes of plants and animals will make it faster and easier to create climate-resilient crops and livestock, avoiding many of the limitations of previous breeding and gene-editing techniques. Another promise is that the resulting products may be more attractive to the public, as they will often not contain DNA from other organisms — and will not be labeled as bioengineering. (It’s worth noting that CRISPR can also be used to create transgenic plants and animals.)
“It’s very exciting to see these products emerging, because they have real and extremely important impacts, especially as we deal with a changing climate and expanding populations,” says Doudna, a professor of biochemistry at the University of California, Berkeley.
However, there remain considerable obstacles to the development and commercialization of new transformative crops and animals, as well as limits on the extent to which the tool can actually help farmers and communities in regions that become excessively hot, dry or wet in the coming decades.
The next CRISPRed foods
In recent years, the US Department of Agriculture (USDA) has relaxed its governance and labeling rules for genetically modified foods, paving the way for many changes made with CRISPR.
The department still oversees and requires disclosures for transgenic plants and animals. But it has determined that it will not regulate foods when gene-editing tools such as CRISPR are used to make “a single modification that could have been achieved through conventional breeding” carried out over a longer period.
“We’re just providing a characteristic that could have occurred naturally,” Doudna says of the regulatory distinction. “It’s just that we’ve accelerated this process with CRISPR.”
The USDA confirmed to companies or research groups that several dozen crops developed with CRISPR would be exempt from regulation, according to an analysis of public documents by MIT Technology Review.
In this context, the use of CRISPR and similar technologies will be crucial to feeding a growing global population without dramatically expanding the use of land, fertilizers and other resources dedicated to agriculture, says Chavonda Jacobs-Young, USDA chief science officer. Jacobs-Young attended the conference at UC Berkeley and also spoke with MIT Technology Review.
“We need high-tech tools,” she says. “These tools will be critical to ensuring a safe, abundant, tasty… and affordable food supply.”
Conventional breeding methods — which include crossing plant and animal varieties or using radiation or chemicals to create mutations — are imprecise processes. They can generate several changes throughout the genome that are not always beneficial, requiring a lot of trial and error to identify improvements.
“The exciting thing about CRISPR for gene editing is that you can make changes exactly where you want,” says Emma Kovak, senior food and agriculture analyst at the Breakthrough Institute. “It saves a lot of time and money.”
Despite the power and precision of CRISPR, considerable work is still needed to identify the correct part of the genome, assess whether the changes bring the desired benefits, and, crucially, ensure that edits do not compromise overall plant health or food safety. .
Improved gene editing tools have also helped revive and accelerate research to better understand complex plant genomes, which are often several times longer than the human genome. This work is helping scientists identify the genes responsible for relevant traits and the changes that could provide improvements.
As research in this area progresses, Doudna says we will increasingly see crops altered to increase resilience to climate change. “In the future, as we discover more about the fundamental genetics of traits, CRISPR could be a very practical application for creating the kind of plants that will meet these imminent challenges,” she says.
Practical plants and sustainable cows
IGI’s efforts to develop a more drought-tolerant type of rice illustrate both the potential and challenges ahead.
Several research groups have used CRISPR to disable a gene that influences the number of small pores in plant leaves. These pores, known as stomata, allow the rice to absorb carbon dioxide, release oxygen and eliminate water to regulate its temperature. The expectation is that, with fewer stomata, plants will be able to retain more water to survive and grow in drier conditions.
But this balance has proven complicated. In previous research, the gene called STOMAGEN was deactivated, eliminating about 80% of pores, which actually reduced water loss. However, this also impaired the plants’ ability to absorb carbon dioxide and release oxygen, both of which are essential for photosynthesis.
The IGI researchers focused on a different gene, EPFL10, which had a less radical effect, reducing the number of pores by about 20%. According to studies published by the group, this modification helped plants preserve water without affecting their ability to regulate temperature or carry out gas exchange.
“It’s an advance in genetic improvement,” says Doudna about CRISPR. “We can adjust the amount of these pores, increasing or decreasing certain genes… to levels that actually support plant growth and allow farmers to produce rice with the quality and yield they need, but without the loss of water.”
The organization is also exploring ways that CRISPR can act more directly on climate change, including a research program aimed at reducing methane expelled by livestock, the main source of greenhouse gas emissions related to livestock farming.
IGI is collaborating with researchers at the University of California, Davis, and other institutions to investigate whether CRISPR and other emerging tools could be used to modify microorganisms in the stomachs of cattle to reduce production of this potent greenhouse gas.
Several research groups and startups are working on reducing these emissions through food additives, generally derived from algae. However, the expectation is that changes in the cattle microbiome are permanent and hereditary, says Brad Ringeisen, executive director of the IGI.
“If we are successful, this could potentially be applied to almost every cow in the world,” he says.
Labeling and safety
Kovak says there are still many challenges that could delay the development of CRISPR-edited animals and plants, including regulatory hurdles for products that introduce foreign DNA or more complex modifications. Ongoing disputes over the intellectual property rights of the tool and its emerging variants, in addition to the costs and requirements that companies must bear to use the technology, also hamper progress.
Doudna herself is at the center of a complex and bitter dispute with the Broad Institute over ownership of key CRISPR patents. (Broad is affiliated with MIT, which owns MIT Technology Review.) Each group has secured multiple patents in multiple countries for certain aspects and varieties of the tool.
These ongoing legal disputes have created complexity and uncertainty for companies wanting to use CRISPR to develop commercial products.
Doudna has founded or co-founded several startups, including Caribou Biosciences, which has sublicensed the use of certain CRISPR patents for agricultural applications. She did not respond to a follow-up question about this issue before the story closed.
“While we have seen a lot of progress in a relatively short time, control of the various CRISPR patents by a few entities has sometimes slowed or prevented some agricultural products from reaching the market,” IGI’s Ringeisen said in an email response.
However, he adds that there is continued progress in discovering and using related gene editing tools that are not tied to patents.
Meanwhile, natural foods retailers, critics of genetically modified organisms and others have sharply criticized the USDA’s position on the governance and labeling of genetically altered foods. They claim that altered cultures have caused harmful environmental consequences and that the rules do not provide enough transparency for consumers to make informed decisions about the food they buy and consume.
Doudna emphasizes the importance of cautious use of CRISPR and similar tools, but believes the US has found the right balance in its regulatory and labeling approach.
“Regulation really is based on science,” she says. “Instead of focusing on how this plant or crop was created, the question is: What is the end product?
” She says IGI has strived to act as a “voice of reason” on these issues, helping to quell fears and misunderstandings by providing scientific information about how CRISPR can be used to treat human diseases, help farmers adapt to climate change or face other threats to people’s lives.
“From the beginning, it was clear that this was a powerful tool that could be misunderstood and misused,” she says. “But it also has tremendous potential to help us address many of these challenges.”
(fonte: MIT Technology Review)
