Researchers have long believed that they could use xenotransplantation (transplant between different species) with our porcine friends, as their physiology is the closest match and they don't carry the same ethical baggage as other members of the animal kingdom, such as chimps or baboons.
Scientists have been looking at the possibility of using pig organs in xenotransplantation for a while now - their organ size is similar to humans, they reproduce quickly and they can be genetically manipulated to reduce the risk of rejection.
Concerns over these infections being passed from pig to patient have been a major stumbling block in the quest to find an alternative to human organ donation.
They implanted the new DNA into an embryo that was implanted into a surrogate sow who then gave birth to completely healthy piglets. "This is a great step forward for xenotransplantation", says Joachim Denner of the Robert Koch Institute in Germany. They started with cells from adult pigs, and used an electrical jolt to fuse them with pig ova whose DNA had been removed.
Recent advances in CRISPR gene editing have enabled the simultaneous editing of multiple sites in the genome, and Yang and her team found that they could indeed successfully remove all PERV copies from primary pig cells.
George Church, a Harvard Medical School geneticist who co-founded eGenesis and is a co-author of the paper, said piglets would need to be roughly four months old for their organs to be used for transplants.
This has now been cleared, in a world first which has seen live pigs genetically engineered to eradicate the virus. "The real breakthrough will be when people are moving around for years with pig organs, only then will we really know that it's safe and effective". Unfortunately, the long list of people who wait for lifesaving organ transplants in the United States underlines a shortage of donors.
Scientists have edited the pig genome to deactivate a family of retroviruses.
Organ transplantation is a controversial topic at the best of times.
These are the first Perv-free pigs.It is an issue that emerged in the early 1980s when surgeons put a pig heart into a baboon. Researchers now face the task of removing the genetic material in pigs that may "provoke the human immune system" or create "toxic interactions with human blood".
Society might have a broad acceptance of consuming them in the form of pork and bacon, but the idea of stitching pig tissues into our bodies is a whole other ball game.