As the popular children’s poem goes: “This little piggy went to market.”
Now that the Food and Drug Administration has authorized letting gene-edited pigs enter the human food chain, that may be the case for a vastly different sort of pig than the one in the Mother Goose poem.
As a starter, German-style sausages, made from five 2-year-old genetically edited pigs, which were cooked up earlier this month at Washington State University, were a test case. Jon Oatley, a professor in the college’s School of Molecular Biosciences, said he went through the FDA food-use authorization process for the pigs to show that food made from the animals using a CRISPR application is safe to eat.
Oatley explained that the “base genetics” of the pigs was a mix of commercial breeds and reflective of what a standard pig operation would have.
“The CRISPR editing application is a specific gene that targets conserved in all mammals, so this will definitely be relevant to all types of pigs,” he said.
For Oatley and his fellow researchers, the overall goal is to develop desirable traits for improved food production and meat quality, which will help feed the planet’s growing population. This, in turn, is an important goal for boosting protein sources in developing nations.
But the research goes beyond pigs.
“We are working as well on cattle, goats, and sheep, all of which are important food-producing animals,” he said. “But the research on pigs has advanced faster compared to other livestock we work with because they bear litters and the generation interval is comparatively faster.”
Pork is the most widely eaten meat in the world. Pigs are usually butchered for meat at only 5 1/2 to 6 months of age, whereas beef cows are generally butchered at 30 to 42 months.
The FDA authorization is investigational and limited to the pigs in Oatley’s research.
“But in the future, we will be seeking food-use authorization for the other species as well,” he said.
As for food safety, Oatley said there is no concern about food safety from the CRISPR edits that were made.
“The DNA changes were not in any part of the genome that would make the animals more susceptible to infectious diseases compared to normal non-edited pigs,” he said. “The USDA FSIS (Food Safety and Inspection Service) inspected the animals prior to processing and the carcass after processing using the standards applied to all processed livestock and found no abnormalities.”
Oatley also confirmed that as long as standard food-safety practices are used in raising, slaughtering, packaging, and cooking the meat, the pork will be free of foodborne pathogens.
What is this all about
In the gene-editing technology, known as CRISPR that Oatley used — a 2-year process that cost $200,000 to collect data for the FDA authorization — the male pigs were “gene-edited in a way that let researchers use them to produce offspring with traits from another male pig. That was done by making the pigs sterile by knocking out a gene called NANOS2, which is specific for male fertility. With that much done, the animals were implanted with another male’s stem cells that created sperm with those other males’ traits, which can be passed on to the next generation.
To see a YouTube video about CRISPR, go to https://www.youtube.com/watch?v=2pp17E4E-O8.
The offspring of the pigs in Oatley’s research are not gene-edited and have not yet been reviewed by the FDA for possible inclusion in the food chain.
But Oatley said that in the future, the research team will be seeking food-use authorization for the other species as well.
It won’t happen overnight, of course. Oatley conceded that scaling up to a large production setting is one of the next challenges ahead.
“My estimation is that we can achieve commercial scaling within 5 years,” he said.
Some are referring to this procedure as a “high-tech form of selective breeding,” and the pigs as “surrogate sires.” Traditionally, producers had to rely on selective breeding . . . or even just time, often a long time, . . . for the sort of improvements that Oatley and his fellow researchers achieved.
The pigs are not genetically modified animals (GMOs), which involves a different technology that involves inserting DNA from an outside species into the genome of an organism.
In the case of genetically modified salmon, for example, the salmon has an added gene from the ocean pout fish that acts as an “on switch” to produce the year-round growth hormone. This, therefore, shortens the time it takes to grow a mature salmon.
Oatley said that the GMO salmon possess foreign DNA that could never have arisen in nature without humans purposely inserting the foreign DNA.
“Our gene edits did not involve the incorporation of foreign DNA, rather they were changes that could arise in nature,” he said. “Gene-editing is a modern cutting-edge technology that works only within a species’ own DNA and that can make changes that could come about naturally or through traditional breeding practices,” he said.
A genome is the complete set of DNA (genetic material) in an organism. In the case of humans, for example, almost every cell in the body contains a complete copy of the genome. The genome contains all of the information needed for a person to develop and grow.
Two sides of the coin
Any artificial manipulation that invades living cells for the purpose of altering its genome in a direct way, including gene editing, constitutes genetic engineering, according to a Friends of the Earth report (https://foe.org/news/gene-editing- risks-health-environment/).
Going one step further, the report points to the importance of human acceptance of gene editing.
“While it is critical for more scientific studies to be conducted about the specific impacts of the unintended consequences of gene editing on agricultural systems, ecological systems, human and animal health, the discussion regarding the use of gene editing in agriculture also needs to go further than a science-based risk assessment to encompass wide public discussion about the future of agriculture.”
The report also calls for more safety assessment and oversight of gene editing..
The Institute for Responsible Technology’s website describes gene editing as a cheap, easy, prone to side effects, poorly regulated and can permanently alter nature’s gene pool — a recipe for disaster. Go here for a video outlining the organization’s concerns.
As for the need to label genetically edited foods, Oatley said that currently labeling is not required, which he believes is the best way to go.
“The DNA changes we are making with CRISPRs are changes that can arise in nature to be propagated via selective breeding, but it would take screening thousands of animals to identify those with the desired combination of genetics and then decades to breed out a pure line for eventual use in a production setting,” he said. “Therefore, from my perspective, if a label would be required on edible products from an animal with CRISPR edited DNA, we should also apply a label to all products because traditional selective breeding also generates genetic combinations that have arisen by way of human intervention.
Charlie Arnot of the Affordable Center for Integrity describes gene editing as one of the many agricultural tools one can use to produce the healthy food consumers expect using fewer natural resources.
“It can allow breeders to make genetic improvements more quickly and precisely than other breeding methods,” he told Food Safety News in an earlier interview. “Being able to make improvements more quickly and precisely to produce the food we need with less environmental impact is an important social benefit.”
He also said that gene editing has “tremendous potential to help farmers grow the food we need using less land, water, chemicals and other resources.
The Coalition for Responsible Gene Editing in Agriculture continues to refine the Framework for Responsible Use of Gene Editing in Agriculture as a market assurance program that organizations can follow to demonstrate their commitment to the safe and transparent use of gene editing technology.
“We designed the process with a focus on continuous improvements and an annual review to ensure the program remains credible, workable and affordable and the technology and applications evolve over time,” said Arnot.
When Oatley looks to the future, he believes that over the next 30 to 50 years, food animals will need to be more resilient in changing climate conditions and more efficient in how inputs like water and feedstuffs are converted to outputs for human consumption.
“Conventional production practices will not be sufficient to feed the global population in 2050,” he said. To address the future of food security, the adoption of biotechnologies like CRISPR gene editing will be critical.
“We’re just driving to the ballpark,” said John Dombrosky, CEO of Ag Tec Accelerator in an interview with Bloomberg News. “Gene editing will be free to do tremendous things across the ag continuum, and the promise is just gigantic. We’ll be able to fine-tune food for amazing health and nutritional benefits.”
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