Although both died within a week and appeared to be normal, the baby animals had genetic material from cynomolgus monkeys in their heart, liver, spleen, lung and skin.
Scientists said the research, which required more than 4,000 embryos to get the piglets, aims to find ways of growing human organs in animals for transplantation.
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Five-day old piglet embryos had monkey stem cells injected into them that had been adjusted to produce a flourescent (sic) protein, allowing researchers to find out where the cells ended up. […]
The 87-year-old told the Sunday Telegraph: “If the result of xenotransplantation is satisfactory with porcine kidneys to humans then it is likely that hearts would be used with good effects in humans within a few years.
“If it works with a kidney, it will work with a heart... That will transform the issue,” he explained.
Pigs’ hearts have a similar anatomy to those of humans, so they are used as models for developing new treatments. Heart failure is considered a global pandemic, with at least 26 million people affected around the world. It’s hoped that using pigs’ hearts could help revolutionize how doctors combat the disease.
https://www.rt.com/news/466766-pigs-heart-human-transplants/
The late Lewis Grizzard often wrote and talked about the pig valve in his heart.