“Jennifer and I share the same views on climate and how big a problem it is worldwide,” said Brad Ringeisen, executive director of the Institute for Innovative Genomics (IGI). “We just don’t want to sit idly by.”
Climate experts overwhelmingly agree that the only way to truly combat climate change is to reduce the amount of greenhouse gases we put into the air when we burn fossil fuels to generate electricity or to power trains, planes and cars. But humans are already pumping so much pollution into the atmosphere that heats the planet, and we also need to find ways to clean up some of the existing mess and prevent more catastrophic climate change. One of the ways to achieve this is through plants. Plants naturally absorb carbon dioxide, a common greenhouse gas, during photosynthesis. Eventually, they transfer this carbon into the soil.
CRISPR can be used to make precise changes to a plant’s genome to produce desirable traits. In IGI’s carbon removal mission, there are three targets for gene editing. First, it tries to make plants’ photosynthesis more efficient so they can better capture as much carbon dioxide as possible. Second, IGI is interested in developing crops with longer root systems. Plants transfer carbon into the soil through their roots (and from the rest of their bodies when they die). Longer roots can deposit carbon deep in the soil so it can’t be released into the atmosphere again as easily. A similar effort is underway to influence the genes of plants and develop crops with stronger root systems at the Salk Institute for Biological Studies, which received $30 million in 2020 funding from the Bezos Earth Fund.
This brings us to the third aspect of IGI research: improving the ability of soils to store, rather than release, greenhouse gases. Soils typically don’t store carbon for very long. It escapes back into the atmosphere through respiration as soil microbes break down plant matter. And techniques used in modern agriculture, such as tillage, speed up this process, causing soils to lose more carbon. One potential outcome of IGI’s CRISPR research, according to Ringeisen, is that a product could be added to soil to foster a soil microbiome that retains carbon for longer.
These are heavy tasks, and there is still a long way to go. $11 million from the Chan-Zuckerberg Initiative funded the three-year research, which Ringeisen expects to have “a real impact within seven to ten years.” Even if they successfully genetically engineer plants and soil microbes within this time frame, scaling up to have a meaningful impact on climate will remain a formidable challenge.
“Plants are already extremely efficient carbon-fixing machines, the result of millions of years of evolution, so I still don’t believe CRISPR can do the work we need,” César Terrer, an assistant professor at MIT, wrote in an email. There’s a lot of work being done at scale to improve carbon sequestration.”
Terrer was not involved in the project, but he was a former researcher at Lawrence Livermore National Laboratory, one of the participating institutions. “If anyone can do it, it’s them.” Transforming nature to help us combat climate change could distract from the more pressing need to reduce greenhouse gas pollution in the first place.
Agriculture is already responsible for its own huge carbon footprint – much of which comes from livestock and fertilizers. Rice cultivation is also a big culprit in methane emissions, as wet paddy fields are ideal homes for methane-producing microbes. IGI is also working to address this issue, again looking at altering the root system and microbes in the soil.
According to Ringeisen, the rice genome is easier to manipulate than other crops, in part because it has been studied a lot and is well understood. One of the scientists involved in the IGI program is Pamela Ronald, best known for his research using a different type of genetic engineering (more like precision breeding) to develop rice varieties that survive flooding longer than other types of rice. The rice is now grown by more than 6 million farmers in India and Bangladesh, according to Ronald’s lab at UC Davis.
IGI’s work doesn’t stop with rice. Sorghum is another prime candidate for gene editing to boost carbon removal, according to Ringeisen. He also hopes that any new varieties they develop will give farmers additional incentives, such as better harvests from more efficient photosynthesis. But that’s still years away. IGI hopes to begin international field trials with farmers about three years after their work on CRISPR rice begins.