CRISPR poised to transform livestock breeding in Africa

By Joseph Opoku Gakpo

March 6, 2018

Gene editing will dramatically transform livestock breeding in Africa for the better in the next few years, predicted Dr. Andrew Kiggundu, a Ugandan agricultural scientist. CRISPR and other gene editing technology will have a much greater impact on animal production than crops due to the nature of livestock disease in Africa, said Kiggundu, project manager of the Institute for International Crop Improvement at the Donald Danforth Plant Science Center in St. Louis, Missouri.

More than 50 percent of the farmland in sub-Saharan Africa is used for grazing animals, which are extremely valuable assets to rural families. They are a crucial source of dairy product protein, and provide transport and other support on farms. But diseases like trypanosomiasis, which causes fever, weight loss and sometimes death in cattle, are causing many families to lose their animals.

The peculiar nature of diseases that attack animals in Africa makes it difficult and expensive to treat them, Kiggundu explained in an interview with the Alliance for Science. But with the introduction of the CRISPR technology, it will become easier to precisely develop preventative measures.

“There are diseases that are endemic to Africa. Sometimes, because of the variability of the pathogen, the vaccine prevents it in Kenya, but it doesn’t work in Zambia, which means vaccine development must continue to be able to catch up. The normal pharmaceutical industry doesn’t want to go those lengths because the vaccine is expensive to develop and how much will they be able to sell?” he noted.

“If CRISPR is able to make cows that are resistant to trypanosomiasis, for example, it will change things… CRISPR is now going to bring animal genetic engineering forward a lot faster, and we are going to start to see CRISPR animals,” he added.

CRISPR allows scientists to easily alter DNA sequences and modify gene function by editing the genome of plants and animals. It has the potential to correct defects in living organisms to stop the perpetuation of diseases and non-desired traits.

The full meaning of CRISPR is Clustered Regularly Interspaced Short Palindromic Repeats. These are specialized DNA stretches in single celled organisms with an associated enzyme, Cas9, which works like a pair of molecular scissors capable of cutting DNA strands. When introduced in multi celled organisms, they have the capacity to edit the genes to suit specific purposes.

Kiggundu, who previously served as director of the Biotechnology Research Center at the National Agricultural Research Organization (NARO) in Uganda, believes the emerging breeding technology will be most useful in animals because of the complicated improvement procedures that livestock breeding requires.

“CRISPR will be a lot more valuable in animal genetic improvement because breeding animals is more complicated than breeding crops,” he explained. “We understand plant genetics and already can work a lot more predictably with plant genetics than animals… CRISPR seeks to correct genetic mistakes that have occurred through genetic evolution… … and will be of much more benefit in genetic animal improvement than crops.”

But Kiggundu expressed worry about the complicated regulatory processes that such products must navigate before they are approved and allowed on the market. He is, however, confident that the process will change with CRISPR technology because of the long, drawn-out nature of the discussions already occurring around the regulation of this new tool. Still, he warned that the debate might go on for a while longer.

“I think a clear definition of CRISPR as GMO or GE is taking time to evolve because those who earlier coined the term [GMO] are feeling that they should not be the ones to coin it this time, and that a clear distinction should evolve,” he observed. “Let’s see how it evolves.”

One major distinction is that gene editing occurs within a species’ genome and typically does not involve the introduction of a gene from another species, as occurs with genetic modification.

Barring any regulatory hitches, DuPont Pioneer’s waxy corn will be the first commercialized CRISPR/Cas9 product, and is expected to be on the market in about two years. Research is also under way on tomatoes, canola, camelina and other crops. A polled, or hornless, dairy cow has also been developed, and research continues on pigs resistant to swine flu and cows that can withstand higher temperatures.