science-1336664_640Welcome to the Brave New World of medical research! The Obama Administration announced on Thursday, August 4, that the federal government will soon begin funding research in which scientists create human/animal hybrids, called chimeras, under “certain carefully monitored conditions.”

Let me explain:  Your tax dollars will now be used to fund laboratory research which uses human stem cells to create animal embryos that are partly human.  So there may be human/pig hybrids, or human/mouse or human/puppy.

It’s not that scientists are not aware of the potential controversies inherent in such research. In September 2015, the National Institutes of Health established a moratorium on funding chimera research, because it could raise ethical concerns. Following establishment of the moratorium, NIH has reviewed the state of the science and also convened a workshop in November 2015, bringing together leading experts in the field of chimera research and animal welfare.

National Public Radio reported on how the proposed research could reach beyond what is standard scientific practice:

One issue is that scientists might inadvertently create animals that have partly human brains, endowing them with some semblance of human consciousness or human thinking abilities. Another is that they could develop into animals with human sperm and eggs and breed, producing human embryos or fetuses inside animals or hybrid creatures.

But scientists have argued that they could take steps to prevent those outcomes and that the embryos provide invaluable tools for medical research.

NPR outlined the protections which the NIH intends to put in place, denying research funding in those areas which are ethically questionable.

The policy proposes prohibiting the introduction of certain types of human cells into embryos of nonhuman primates, such as monkeys and chimps, at even earlier stages of development than what was currently prohibited. The extra protections are being added because these animals are so closely related to humans.

But the policy would lift the moratorium on funding experiments involving other species. Because of the ethical concerns, though, at least some of the experiments would go through an extra layer of review by a new, special committee of government officials.

That committee would, for example, consider experiments designed to create animals with human brain cells or human brain tissue. Scientists might want to create them to study neurological conditions such as Alzheimer’s and Parkinson’s diseases. But the experiments would undergo intensive scrutiny if there’s any chance there might be a “substantial contribution” or “substantial functional modification” to an animal’s brain.

In addition, the NIH would even consider experiments that could create animals with human sperm and human eggs since they may be useful for studying human development and infertility. But in that case steps would have to be taken to prevent the animals from breeding.

Dr. Carrie D. Wolinetz, NIH’s Associate Director for Science Policy, called the research “very important to our understanding of disease,” but promised that there would be an extra set of eyes on these projects because of the ethical concerns associated with them.


Father Tad Pacholczyk, Education Director of the National Catholic Bioethics Center, wrote in February 2016 about the Catholic Church’s concerns regarding chimera research. In “Human Organs From Pigs: Is It Kosher?”, Father Tad first acknowledged that if ethical standards are maintained, there could be positive benefits derived from the research:

Despite our initial hesitations, certain kinds of human/animal chimeras are likely to be justifiable and reasonable. This comes into focus when we recognize, for example, how thousands of patients who have received replacement heart valves made out of pig or cow tissues are already themselves a type of human/animal chimera. For many years, moreover, scientists have worked with chimeric mice that possess a human immune system, enabling them to study the way that HIV and other viruses are able to infect cells.

We routinely use animals to address important human needs. We eat them and make clothing out of them. We keep them in zoos. Utilizing them for legitimate and important medical purposes like organ generation and transplantation should not, broadly speaking, be a cause for alarm.

BUT (and this is a big caution) Father Tad goes on to list some of the pitfalls which could make the research ethically problematic:

Yet significant technical and ethical hurdles remain before growing organs in pigs is likely to be feasible. The science is still in its infancy, and researchers have yet to figure out how to make human cells co-exist in a stable fashion with animal tissues. There are abundant concerns about the possibility of transmitting animal viruses to humans especially considering how readily other viruses like avian flu have been able to jump from birds to humans.

Even assuming these kinds of risks are able to be minimized, and pig/human chimeras could be safely produced, there would still be several ethical issues to consider. One concern involves using stem cells from human embryos as part of the process of making pig/human chimeras. Typically scientists try to generate chimeras by adding human embryonic stem cells to animal embryos, which then grow up and develop into chimeric animals. Destroying young humans in their embryonic stages for their stem cells is gravely objectionable, so creating chimeras could be ethical only if alternative, non-embryonic sources of stem cells (like adult stem cells or induced pluripotent stem cells) were utilized for the procedure.

The technology might also lend itself to other unethical practices, like trying to create a pig that could produce human sperm or eggs in its genitalia. Similarly, if human nerve cells were incorporated into a developing pig brain in such a way that the animal developed what appeared to be human brain structures, some have noted there could be questions about the occurrence of intelligence or self-consciousness or other facets of human identity in the animal. Although such concerns seem farfetched, given the dearth of knowledge about the “scaffolding of consciousness,” it seems reasonable to limit this kind of experimentation.

Read the rest here.


The National Institutes of Health have invited public comments on the proposed new policy. Concerned citizens have thirty days in which to respond (responses must be submitted by 11:59 p.m. on September 4, 2016), and the NIH could start funding projects as early as January 2017.

It’s an important issue, and one on which the federal government needs to hear, not only from the scientific community, but also from concerned, courteous and well-prepared Catholic and Christian thinkers. As Father Tad Pacholczyk explains,

“…We should continue to insist that cutting edge biomedical research remain in active dialogue and interaction with sound ethics. The expanding study of human/animal chimeras challenges us to reflect carefully on the morally appropriate use of these novel and powerful technologies, so that human dignity will not be harmed, subjugated, or misappropriated in any way.” 

Click here to submit your comment to the NIH.

Image:  Pixabay