Consumers who like their meat lean now have the help of genetic engineering to grant their wish.
Scientists from South Korea and China have used genetic editing to design a “double-muscled” pig that would produce more, leaner meat, Nature reports. The genetic engineering is less drastic than typical genetic modification because the scientists have only edited one of the pig’s genes instead of transplanting genetic information from another species—an important distinction for the scientists involved who hope it will help both consumers and regulators accept it as safe. “We could do this through breeding,” Jin-Soo Kim, who is leading the work at Seoul National University, told Nature, “but then it would take decades.”
The “double-muscled” pig is created by introducing a mutation into the pigs’ genetics that keeps the muscles developing beyond the point they would naturally. The researchers edited the cells of a pig fetus, eventually creating 32 piglet clones with the new genetics. But while the new pigs have the benefits—leaner and more meat per animal—they also exhibited some problems. Of those 32 piglet clones, only 13 lived to see their 8-month birthday, only two were alive on July 2, and “only one is considered healthy.”
The researchers’ plan would not be to make meat from these pigs, the researchers told Nature, but rather to sell their sperm to be used for impregnating normal pigs. This would create a pig that is both healthy and has more muscle than a normal one, though less than the ones with edited genes.
Currently, there are no genetically engineered animals that have been approved for human consumption, but it’s not for a lack of trying. AquaBounty Technologies have developed a type of salmon that can grow twice as fast as its conventional counterpart; it has been dubbed a “FrankFish” by environmental groups and has been under review with the FDA for nearly 20 years. And the University of Guelph in Canada developed an Enviropig, which can digest feed more efficiently and excrete more environmentally friendly feces, but the project ended thanks to consumer resistance.
The pork industry in the US, however, has another way to achieve a leaner pork. Some hog farmers use ractopamine, a growth promoting feed additive, to up the amount of meat, and especially lean meat, on a hog. The drug, which works through different chemical mechanisms than the genetic engineering, is not legal in China, Russia and the EU, though, and questions remain about its safety for the animals and the humans who consume them. (It is approved for use in South Korea.)
But unlike ractopamine, which has not been shown to change taste, the impacts of the genetic engineering on taste are disputed. It may create a “tougher meat product,” says Dr. Steve Larsen, director of pork safety for US industry group the National Pork Board. But Seoul National University’s Kim tells Quartz he disagrees. “Belgian Blue,” the cow breed with naturally occurring double-muscling, “is well known for its tender meat,” he says.
Whether or not genetically engineered double-muscled pigs comes to the US, says the National Pork Board’s Larsen, depends on a review from the US Food and Drug Administration and whether or not people want to buy it. “Let the market dictate its use,” says Larsen.
In China, where ractopamine is banned but demand for pork is growing, the market is likely to say yes.