Caribou Biosciences and DuPont Pioneer Develop New Method to Comprehensively Map the Off-Target Activity of CRISPR-Cas9 Across Entire Genomes

The full study, entitled “Mapping the genomic landscape of CRISPR–Cas9 cleavage,” was published today in Nature Methods and details the biochemical method developed by Caribou and DuPont Pioneer scientists to comprehensively map CRISPR-Cas9 cleavage sites within the genome. Importantly, this information can be used to precisely measure the off-target effects of CRISPR-Cas9 genome editing in cell-based applications. Overall, this method will allow researchers to more effectively select CRISPR-Cas9 targets and delivery methods with maximum accuracy and specificity, thereby overcoming some of the concerns associated with potential off-target effects of CRISPR-Cas9.

This new method is expected to have broad applicability as it can be used to comprehensively detect CRISPR-Cas9 cleavage sites across the genome of any organism. The SITE-Seq method, in conjunction with cell-based validation methods, will constitute a robust pipeline for selecting CRISPR-Cas9 reagents for research or product development.

“This research marks a significant step towards the confirmation of CRISPR-Cas9 as a safe and effective gene-editing tool. By providing researchers with a way to accurately map the genomic landscape of CRISPR–Cas9 activity, we can reduce the occurrence of off-target effects by selecting for targets with the highest possible activity and specificity,” said Dr. Rachel Haurwitz, President and CEO of Caribou. “We are delighted at this latest demonstration of the valuable collaboration between Caribou and DuPont Pioneer scientists who are advancing the development of CRISPR-Cas9 applications.”

“The SITE-Seq research is an excellent proof point of productive collaboration between Caribou and DuPont Pioneer for the advancement of CRISPR-Cas technology,” said Dr. Neal Gutterson, vice president, Research & Development at DuPont Pioneer.

About Caribou Biosciences

Caribou is a leading company in CRISPR genome engineering founded by pioneers of CRISPR-Cas9 biology based on research carried out in the Doudna Laboratory at the University of California, Berkeley. Caribou’s tools and technologies provide transformative capabilities to therapeutic development, agricultural biotechnology, industrial biotechnology, and basic and applied biological research. For more information, including information about obtaining research and commercial licenses, visit www.cariboubio.com and follow the Company @CaribouBio. “Caribou Biosciences” and the Caribou logo are registered trademarks of Caribou Biosciences, Inc., and “SITE-Seq” is a trademark of Caribou Biosciences, Inc.

DuPont Pioneer is the world’s leading developer and supplier of advanced plant genetics, providing high-quality seeds to farmers in more than 90 countries. Pioneer provides agronomic support and services to help increase farmer productivity and profitability and strives to develop sustainable agricultural systems for people everywhere. Science with Service Delivering Success^®

DuPont (NYSE: DD) has been bringing world-class science and engineering to the global marketplace in the form of innovative products, materials, and services since 1802. The company believes that by collaborating with customers, governments, NGOs, and thought leaders, we can help find solutions to such global challenges as providing enough healthy food for people everywhere, decreasing dependence on fossil fuels, and protecting life and the environment. For additional information about DuPont and its commitment to inclusive innovation, please visit www.dupont.com.

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