Gene-Editing Cows’ Gut Microbes May Curb Climate Change

In a groundbreaking initiative, scientists are exploring a range of methods to mitigate methane emissions from ruminants—a significant contributor to greenhouse gases. While feed supplements, selective breeding, and vaccines are among the explored strategies, a novel approach involving gene-editing of microbes could revolutionize the field. Professor Ermias Kebreab from the University of California Davis asserts that this high-risk, high-reward strategy could be a game-changer. “If it works, you won’t have to do anything else,” he says.

Methane, a potent greenhouse gas, is produced in the rumen, a specialized stomach compartment in ruminants like cows and sheep. Here, microbes break down complex carbohydrates, generating gases that methanogens convert into methane. This methane is then expelled by the animals through belching. Professor Kebreab, along with a team of academics, is part of a $70 million initiative funded by the TED Audacious Project. The seven-year endeavor, titled ‘Engineering the Microbiome with CRISPR to Improve our Climate and Health,’ is spearheaded by Dr. Jill Banfield and Dr. Jennifer Doudna at UC Berkeley. The project aims to develop precision microbiome editing to tackle two major issues: childhood asthma and livestock methane emissions.

In an interview with AgFunderNews, Professor Kebreab delved into the specifics of the livestock methane component of the study. He explained that their research on Asparagopsis, a type of red seaweed used as a feed supplement, showed a decrease in methane production not by reducing methanogen populations but by downregulating genes responsible for methane production. This finding has paved the way for the CRISPR project.

The CRISPR approach involves identifying the genes in methanogens responsible for methane production and editing them out. This would allow the microbes to continue using hydrogen as an energy source without producing methane. However, implementing this solution is complex. The CRISPR Cas system needs to be delivered to specific microbes, likely through an oral supplement given to calves before their rumen is fully developed. This early intervention could effectively reprogram the rumen, making it a one-time treatment with long-lasting effects.

The project is a collaborative effort involving UC Berkeley, UC San Francisco, and UC Davis. While UC Berkeley focuses on the CRISPR technology, UC Davis is responsible for the livestock part of the study. The team at UC Davis is collecting microbial samples from cattle rumen and analyzing their DNA, which is then sent to Berkeley for further research. If successful, the final product—likely an oral supplement—will be tested in animal trials at UC Davis’s dairy farm.

Despite the promise of the CRISPR approach, Professor Kebreab emphasizes the need for a multi-faceted strategy to tackle enteric methane emissions. Selective breeding is another promising avenue. In New Zealand, researchers have bred sheep that emit 12-20% less methane, and similar efforts are underway with cattle. However, this method is time-consuming and may not be as immediately impactful as microbiome editing.

Understanding the inherent variability in methane emissions among animals is also crucial. Some animals naturally emit less methane, possibly due to more efficient feed conversion or unique microbiome compositions. Unraveling these mysteries could inform other methane reduction strategies.

Feed additives like Asparagopsis also hold potential. Long-term studies are being conducted to assess the impact of seaweed supplementation on methane emissions throughout an animal’s life cycle. Preliminary results are promising, but more research is needed to fully understand the implications.

In summary, while traditional methods like selective breeding and feed additives offer incremental improvements, the CRISPR approach to microbiome editing could provide a revolutionary solution to methane emissions from ruminants. If successful, this high-risk, high-reward strategy could significantly mitigate one of agriculture’s major contributions to climate change.

Leave a Comment

Your email address will not be published. Required fields are marked *

Scroll to Top