On human-animal hybrid chimeras

Monday, March 6, 2017

Father Alfred Cioffi

English Spanish

At the end of January, a lab in California reported success in inserting live human cells into an early pig embryo (blastocyst), and implanting that chimera into a sow. The pregnancy was interrupted in the first trimester and the pig embryo was analyzed to see if the human cells had integrated into the pig embryo: They had, and they were alive.

One urgent bioethical question this raises is: Do we have a right to create hybrid chimeras between humans and animals that are viable?

One potential benefit would be to insert fully differentiated human cells or tissues into a host animal for the purpose of growing a specific human organ; say, one vitally needed for transplantation (pancreas, liver, heart, etc.). Dozens of patients die daily for lack of transplantable organs, and they could greatly benefit from this.

In this case, a civilized society, seeking to allow scientific research the maximum freedom possible, within ethical standards that respect the dignity of all human life, might approve of creating and/or growing human organs in host animals — except the brain, for it likely is the seat of self-consciousness.

However, by inserting live pluripotent human stem cells (cells that can develop into any organ tissue) into an animal embryo — like the California lab did — those human cells could lodge in the animal tissue that will develop into the brain. By doing so, these human cells could begin to “humanize” that animal brain. Our intuition tells us that this is wrong, that we should not do this. We don’t have a right to create a human brain in an animal, for: Will that brain perceive itself as a human or as an animal? Be held accountable or not for right or wrong behavior?

Last August, the US National Institutes of Health (NIH) sought comments from the general public regarding the relaxation of a moratorium on using federal funds for creating human-animal hybrid chimeras. The overwhelming response from the American people was a resounding: No. But how about private labs, like the one in California; should these experiments be allowed in the U.S. simply because they’re not using federal funds?

The human genome is a patrimony that belongs to all of humanity. Introducing the entire human genome with full potential for expression into a non-human species should not be allowed, out of respect for what belongs to all of us, precisely as humans.

Comments from readers

David Greg Taylor - 03/06/2017 12:49 PM

The great error of Descartes was the idea of repurposing nature. That is only a good idea if the things in nature do not already have a purpose. The scientific method does not formally recognize Formal Cause, which is the form a thing takes to fulfill its purpose. So we find new forms and purposes for things that already have one, and create monsters.

JB - 03/06/2017 10:32 AM

Dear Father Alfred Cioffi and all fellow Catholics, I submit for your perusal that this article should permeate each and every one of you. These "facts" should solidify any desire to stand against anyone that even remotely believes that this is a good thing. Clearly stated: The human genome is a patrimony that belongs to all of humanity. Introducing the entire human genome with full potential for expression into a non-human species should not be allowed, out of respect for what belongs to all of us, precisely as humans. In Unity,

David Greg Taylor - 03/06/2017 12:49 PM: The great error of Descartes was the idea of repurposing nature. That is only a good idea if the things in nature do not already have a purpose. The scientific method does not formally recognize Formal Cause, which is the form a thing takes to fulfill its purpose. So we find new forms and purposes for things that already have one, and create monsters.

JB - 03/06/2017 10:32 AM: Dear Father Alfred Cioffi and all fellow Catholics, I submit for your perusal that this article should permeate each and every one of you. These "facts" should solidify any desire to stand against anyone that even remotely believes that this is a good thing. Clearly stated: The human genome is a patrimony that belongs to all of humanity. Introducing the entire human genome with full potential for expression into a non-human species should not be allowed, out of respect for what belongs to all of us, precisely as humans. In Unity,