Researchers in Beijing found a way to engineer pigs that helps them stay warm and lean.

After 6 months, test litters weighed in with 24% less body fat than regular pigs.

The researchers say the gene editing technique could lead to more efficient pork production, reduced costs for farmers, and healthier pigs.



It sounds almost like an oxymoron: low-fat pork.

Researchers in Beijing have developed a new kind of pig with 24% less body fat than regular, lard-laden swine. The researchers say their technique could help pigs stay warmer, grow faster and healthier, all while reducing costs for breeders.

The successful pig experiment, announced Monday in the Proceedings of the National Academy of Sciences, is a first. In addition to being low-fat, the experimental pigs are unique in one important genetic way: they've got mice proteins in their system.

Pigs have a reputation for being fatty, but they don’t carry the gene that produces brown fat — the stuff that helps most mammals stay warm and burn energy. That’s because they lack the requisite protein, known as UCP1. A team of researchers from the Chinese Academy of Sciences say they’ve found a way to build that protein into baby pigs, creating a new brown fat-carrying pig that can keep itself warmer, without putting on as much "white" fat — or, as you may know it, lard.

Researchers added the protein using CRISPR/Cas9, a gene-editing technology that's kind of like a cut-and-paste function for genetic code. Snip a bit of the UCP1 mice protein into a pig embryo and voila: a pig that develops less fat is born. (Though it's not quite as easy as it sounds in practice: the scientists successfully birthed just 12 male piglets from a total of 2,553 embryos.)

Millionaire's bacon Melia Robinson/Business Insider

The researchers think the lack of brown fat in regular pigs could be a key reason they get so chubby in the first place — it might be part of their feeble attempt to stay warm. Many piglets die from cold stress and the ones who survive often require heat lamps to stay warm in their first weeks of life. Exposed to cold, the UCP1 pigs managed to keep their body temperature stable for hours, while regular pigs' body temperatures dipped lower.

At 6 months old, when the brown fat pigs were finally slaughtered, they had 24% reduced fat content. They didn’t weigh much less than normal pigs, but they had a higher ratio of lean meat on their bodies and thinner back fat as well.

But these piggies are probably not coming to market.

"I very much doubt that this particular pig will ever be imported into the USA,” R. Michael Roberts, an animal sciences professor at the University of Missouri who edited the PNAS paper, told NPR. He also said the pig technology would probably never get FDA approval. Even if it did, Americans would likely be wary of the idea of genetically-altered bacon.

Nutritionists say "low fat" food is not really all that healthy, anyway. Increasingly, sugar is being touted as the waistline-builder in modern diets, and while the saturated fat content in pork still gets a bad rap, health experts tend to encourage healthy overall eating habits instead of fat restriction.

Chinese scientists may have just successfully proven that they can engineer a skinnier pig than nature, but meat lovers probably won’t be frying up the lean bacon anytime soon.