Getting a replacement liver or heart in the future probably won't be as simple as a trip to the butcher shop. But that's not as far-fetched as it may sound.
Surgeon Dr. Nicholas LaRusso at the Mayo Clinic says he's excited about the future prospect of animal organs being transplanted into humans.
"You could envision -- 20 years from now -- everyone who needs a liver having access to one because you would walk into a facility; you take out a pig; and you use the pig liver for the patient."
Dr. LaRusso says genetically engineered pigs are the popular animal for such speculation now. He says the key will be to prevent the possibility of swine-borne illness from affecting humans.
"Any potential diseases that would be unique to animals would not be able to be contracted by a human. This is a big concern now."