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Pope Francis Said to Bless Human-Animal Chimeras

A scientist sought the Vatican’s approval for mixing human cells in animal embryos. And the pope said yes.
January 27, 2016

A Spanish scientist working at the Salk Institute in California told Scientific American that Pope Francis personally blessed his cutting-edge research to mix human cells into animal bodies.

Juan Carlos Izpisua Belmonte, a prominent stem-cell biologist, is engaged in efforts to grow human tissue inside of farm animals such as pigs, sheep, and cows. This type of research is sensitive because scientists have to inject human stem cells into early-stage animal embryos, then try to grow the mixtures inside surrogate animals.

Much of Belmonte’s work occurs in collaboration with a team in the province of Murcia in his native Spain, a sausage- and ham-loving country which is about 77 percent Catholic.

“Spain is a very Catholic country, so we had to go through the Pope. He very nicely said yes.” Belmonte told Scientific American. “Yes. The current Pope. So the Vatican is behind this research and has no problem based on the idea is to help humankind [sic]. And in theory all that we will be doing is killing pigs.”

The Pontifical Academy of Sciences, the Vatican’s scientific body, did not respond to an e-mail seeking to confirm Pope Francis’s position.

After placing human cells into animal embryos, researchers are watching to see what they do. The likely result is that a small percentage of human cells spread throughout the animal’s body. Belmonte’s eventual hope is to channel the human contribution so that it forms a complete human heart or other organ inside a pig or cow. Such an organ could be used to transplant into a needy patient.

While the Catholic Church has opposed research on human embryos, it endorses evolution and generally takes a liberal view on scientific matters. In fact, the Vatican’s position on “human-animal chimeras,” as the mixtures are known, may be more liberal than that of the U.S. National Institutes of Health, which in September instituted a ban on funding chimera research until it can weigh ethical questions associated with it.

Attempts to make this sort of human-animal chimera began only recently. Previously, any added human cells would simply die or the embryo would not live. That changed when Belmonte’s lab and that of Israeli scientist Jacob Hanna each developed new ways of cultivating human stem cells to take on a more “naïve,” primitive state that is able to contribute to the animal embryo.

In 2013, Hanna’s lab at the Weizmann Institute of Science in Rehovot showed these naïve cells could contribute to the bodies of fetal mice, resulting in animals with as much as 15 percent human tissue. Scientists predict many other reports discussing human-animal chimeras soon.

In an interview in December, I asked Hanna what Jewish law had to say about human-animal mixtures.

“I’m not sure. I am a Palestinian Christian,” he said.

(Source: Scientific American)

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