Jon Oatley is trying to devise ways to feed a growing world and to that end, he has genetically modified pigs to be sterile.
“We’re working on a project that we call ‘surrogate sires,’ ” Oatley said. “What it is, is we’re trying to generate male livestock — cattle as well as pigs — that don’t produce their own sperm.”
With the use of an advanced gene-editing technique called CRISPR, famously used in next-generation cancer research, Oatley said he could “knock out” the gene that creates the starting point for sperm production. Once the sterile pig matures, Oatley said, researchers can inject it with the genetic material of a different pig with superior traits, allowing the genetically modified hog to act as a surrogate father for a pig with desirable genetics.
“There’s a stem cell that exists that will produce sperm over and over and over and over,” Oatley said. “We try to take the stem cell out of a male that we would deem to have elite genetics (and) transfer the stem cell in the recipient so that that stem cell can re-establish sperm production over and over and over, in that recipient.”
Oatley explained while livestock all over the world exhibit a variety of traits that allow them to survive in different environments, they don’t always have other qualities breeders deem to be desirable, like high-quality meat or growth potential. In the past, he said, people would bring in a male — or sperm from a male — with these traits to mingle with the genetics of a female that was adapted to survive that environment. While this may help produce hybrid offspring with a combination of genetics that are both desirable and help the animal survive, it is often a costly and clumsy process, not to mention time-consuming. Oatley said it usually takes dozens, if not hundreds, of generations before desirable traits manifest. He said having a group of sterile males who can transmit the genetic material of one superior male allows scientists to influence populations more quickly and on a grander scale than merely breeding for those traits.
Oatley mentioned South American cows by way of example.
“They don’t always have the production characteristics that you’re looking for, like growth or milk production or palatability of the meat — because they’ve been selected for disease resistance,” Oatley said. “Now you can introduce that genetics through this strategy, rather than having to take the animals and ship them around the world.”
With the world population on track to reach 10 billion by the year 2050, Oatley said humanity is in desperate need of more efficient practices to maximize the food supply. Oatley said it is not feasible to merely produce more food, in part because the more the population grows, the less land there is for production. The coming food crisis — and other global concerns such as global warming — can begin to be addressed at the dinner table.
“We have to figure out how to make animals produce a product — whether that’s meat or milk — at today’s nutritional standards that we all want, with less input,” Oatley said. “The genetics of that animal dictate how well it can convert the inputs, like water or food or antibiotics, to a measurable output, which is meat, milk, fiber — that kind of thing.”
While work in genetic modification and animal experimentation are much maligned in the general public, Oatley said this is often due to misunderstanding. He said the pigs WSU works with live in large, clean pens and have a happy, hygienic life. He said the pigs were augmented to be sterile when they were only a single cell but are otherwise no different from any other pig.
“I think the fear factor comes in with people they just don’t understand, so I believe that it really comes down to education,” Oatley said.
Widespread hunger isn’t just some pending humanitarian crisis but a reality in many places throughout the world, Oatley said. Right now, he said, more people in the world die from starvation than from HIV, malaria, and cancer combined. He said to some degree, the ability to dismiss his work as immoral is a position of convenience.
“When the general public is developing opinions about genetically engineered foods, they’re doing it with a full stomach,” Oatley said. “If you went and talked to somebody who has an empty stomach, they have a very different perspective.”