Pig lungs? Gross. Watching this National Geographic video of them pulsate with human blood? Also, gross. The vegetarian in me is reeling. But grossness aside, scientists have found a way to filter human blood through pig lungs in order to eventually use them for organ transplants. This may not be kosher, but hey, it could save lives.In the lab of Dr. Lars Burdorf at the University of Maryland School of Medicine, scientists are experimenting with CRISPR gene editing, a technique that rids pig organs of viruses harmful to humans. While pig-to-human organ transplants are still a ways off, some primate have already undergone successful pig lung transplants. By modifying the pig lungs with human genes, they become able to oxygenate, rather than reject, human blood.With hundreds of thousands of Americans waiting to receive organ transplants, the CRISPR technique could be a game changer, enabling the use of animal organs in humans. According to National Geographic, pigs are the "mammal of choice" as organ donors. Pig organs are fairly similar in size to ours, which makes them ideal. However, they're also infected with PERV (porcine endogenous retroviruses), inactive in pigs, but potentially harmful to humans: PERVs are similar to HIV.So while PERV had rendered pig organs off limits for human transplants, the CRISPR genome editing technique has recently opened up the possibility. This new technology might make vegetarians a bit uneasy, as well those who follow kosher or halal eating codes, but the benefits of killing a pig to save a human life may outweigh the costs.