Pigs are pretty great animals: They're adorable, and unless you're a vegetarian, you probably find them delicious.

Now they might have even more use for humans. According to a study published Thursday in the journal Science, a startup called eGenesis has successfully produced pigs with organs that could be safe enough to transplant into humans.

As it is now, receiving an organ transplant in many cases requires waiting for a donor to die. More than 117,000 people are on the waiting list for organ transplants in the U.S., according to the Department of Health and Human Services. Reaching the top of that list can take years, since only 0.3 percent of people die in a way that allows for their organs to be donated. Because of all this, 22 people die every day while waiting for new organs.

Scientists have studied the possibility of xenotransplantation, or putting organs from one species into another, for decades. Pigs have been a prime candidate as involuntary organ donors since theirs are about the same size as those of humans. But the issues are fairly obvious: Organs from another species can cause the human immune system to react violently. And pigs carry viruses known as porcine endogenous retroviruses (PERVs) that can infect human cells.

Using the burgeoning gene-editing tool known as CRISPR, the team at eGenesis was able to modify pig embryos to delete those viruses. About four months ago, 37 PERV-free pigs were born, 15 of which are still alive and thriving. The pigs' organs will be about the same size as humans' once they reach their maximum size of about 150 pounds.

Actually transplanting those organs into humans is still a ways away, though. Scientists will still have to figure out a way to prevent the human immune system from reacting to another species' organs. But removing the viruses is a big step.

Separately, researchers have also been working toward another possible solution for the donated organ shortage: 3-D printing. Several teams have found ways to 3-D-print organs, but they're used for research purposes, and transplants are still years away.

According to The Atlantic, eGenesis spun out of the lab of Harvard geneticist George Church. Two years ago, Church was able to remove 62 copies of PERVs from pig cells, but this is the first time living piglets have been developed this way.

Published on: Aug 11, 2017