By Morgan Niezing
This article is a part of the University of Missouri's Ag Journalism program's coverage of the 2017 World Food Prize.
DES MOINES, Iowa — CRISPR-Cas was called molecular scissors during a panel at the Borlaug Dialogue International Symposium. That’s much easier than saying the full name: Clustered Regularly Interspaced Short Palindromic Repeats and CRISPR-associated protein. The system, however, may be worth all the syllables.
CRISPR-associated protein 9, or Cas9, works like a search function in genome sequences to find a specific location, then scientists can either delete, edit or replace targeted qualities, working much like a copy editor proofing a story.
“It does take some skill and some knowledge of the genome,” said Neal Gutterson, vice president of research and development at DuPont Pioneer. “If you want to edit a text, you better understand the entire text that you’re going to edit.”
The importance of this for farmers and consumers is that CRISPR-Cas may help speed up the process of getting preferable genetics into food crops. While adding desirable characteristics to plants through traditional breeding can take eight years, CRISPR-Cas is able to get the same results in five years. In addition, CRISPR-Cas can improve multiple genetic characteristics at once.
“CRISPR-Cas is a tool and a tool can be used for many purposes,” Gutterson said. “Pioneer focuses on breeding.”
Genes can be grouped and studied together or in isolation, to see how removing or editing them can result in changes, Feng Zhang, member at the Broad Institute, said.
Nigel Taylor, interim director at the Institute for International Crop Development, outlined how CRISPR-Cas allowed his Ugandan team to successfully edit cassava genes to make the plant resistant to brown streak disease (see story by Eleanor Hasenbeck in this series). Plants infected with brown streak disease must be discarded for any kind of consumption. Using CRISPR-Cas, Taylor’s team was able to isolate and edit the eIF4E gene and combat the disease. In the future, Taylor hopes to use CRISPR-Cas to edit the five other genes in cassava that are also related to brown streak disease.
Some of the crops open for CRISPR-Cas work include cassava, banana, millets, sorghum and sweet potato. In an effort to make crop goals more attainable, DuPont Pioneer has agreements for gene-editing technology use with the Broad Institute of MIT and Harvard University. Editing single genes can take six months or more, and cooperation between multiple institutions helps speed up the process.
Though the technology’s capabilities are astounding, it is not a magic bullet. Reaching small-holder farmers is still a challenge.
“Public opinion is largely unformed and is largely uninformed about CRISPR-Cas and the regulatory framework is largely undefined,” Kevin Pixley, Director of the Genetic Resources Program at the International Maize and Wheat Improvement Center, said.
One way to combat that lack of knowledge is by working with, and training, scientists in the countries that would benefit greatly from CRISPR-Cas. Another way would be to use CRISPR-Cas to genetically modify a prominent African crop such as teff, an annual grass native to Eritrea and Ethiopia, to make it less likely to suffer from lodging, or toppling over due to height.
Next, Gutterson said that explaining the CRISPR-Cas technology to the general public will take a great deal of care.
“We have to put it into a context that is meaningful,” he said. “We have to truly listen to the communities. Ultimately, it is about trust among the farmer, consumer and the people working on CRISPR-Cas.”