Scientists in China have created low-fat pigs using CRISPR-Cas9 gene-editing tool. The animals have about 24 percent less body fat compared with normal pigs.
Pigs With Reduced Body Fat
Pigs lack the UPC1 gene that most mammals have. The gene is involved in regulating body heat in cold temperatures, which explains why piglets are particularly susceptible to cold temperatures. Older pigs are at less risk in cold weathers since they have already stored more body fat that insulates themselves.
In a paper published in the Proceedings of the National Academy of Sciences on Monday, Oct. 23, scientists reported how they produced 12 healthy pigs with reduced body fat. Unlike normal pigs, the low-fat animals also have the fat-burning gene that allowed them to better regulate their body temperatures.
Less Expensive To Raise
Study researcher Jianguo Zhao, of the Institute of Zoology at the Chinese Academy of Sciences, and colleagues said that they created the low-fat animals with the aim of providing pig farmers with animals that would be less expensive to raise and less likely to suffer in cold weather.
The genetic modifications allowed the pigs to survive better in cold weathers, which could save farmers millions of dollars in feeding and heating costs and prevent millions of pigs from getting sick and dying in cold weather.
"UCP1 KI pigs are a potentially valuable resource for agricultural production through their combination of cold adaptation, which improves pig welfare and reduces economic losses, with reduced fat deposition and increased lean meat production," the researchers wrote in their study.
Producing Low-Fat Pigs
Zhao and colleagues created the animals using CRISPR, which gives scientists the ability to make changes in the DNA. Scientists have earlier created mutant ants using CRISPR to study social behavior. Researchers in China also claimed to have used the gene-editing tool to genetically engineer cows so they become resistant to bovine tuberculosis.
In the new experiment, the researchers added a mouse version of the UCP1 KI gene into pig cells, which were then used to create more than 2,553 cloned pig embryos.
The researchers then implanted the cloned embryos into 13 female pigs. Three of the pigs became pregnant and produced the 12 low-fat male pigs. The pigs appeared healthy and normal and at least one of them mated and produced a healthy offspring.
All the animals were, however, slaughtered when they were six months old to allow scientists to analyze their bodies.