Future Tense

What Do You Think About Scientists Creating Human-Nonhuman Hybrids?

The National Institutes of Health wants to know.

scientist lab embryo.
The National Institutes of Health recently proposed changes to the way the agency will oversee research using human stem cells in nonhuman primates.


The U.S. National Institutes of Health wants to support responsible research into human-nonhuman hybrids, and they’d like your help. Sort of.

On Aug. 4, the NIH proposed two changes to the way the agency will oversee research using human stem cells in nonhuman primates. Policy changes like these are required to go out for public review and comment before being implemented, so we’re now entering a 30-day public comment period—everyone with opinions on research into combining humans with other animals has a chance to have his or her say.

That sounds inclusive and democratic, but usually only advocacy groups, concerned organizations, and policy wonks get involved. This isn’t surprising: The call for comments is posted in the rather esoteric Federal Register, a great publication for curing insomnia but not everyday reading for most people. Furthermore, issues like this are usually complex and require at least some background knowledge to understand.

But mashing up humans with pigs, sheep, and other animals is probably the sort of thing that ordinary citizens will want to have a say in. The challenge is, how do you help draw society’s ethical lines if you’ve only got 30 days to comment, and the issue is not straightforward?

The science at stake here involves “chimeras”—animals that are engineered to include both human and nonhuman cells and organs. This technology is increasingly possible with advances in stem cell research and gene editing. And it’s got a lot of scientists excited. Chimeras create brand-new research possibilities that might help us prevent devastating illnesses or understand the health impacts of chemical exposures. They also open the door to the possibility of growing replacement human organs in animals. Think about the possibilities of getting a new heart or lungs without someone having to die first.

Yet not everyone’s excited by the prospect of animals becoming partially “human.” Chimeras raise complex moral and ethical questions around creating part-human animals, questions that have less to do with the “could we?” of science and more to do with the broader “should we?”

Things become especially gnarly when faced with the possibility of chimeras developing part-human brains. Margaret Atwood explored this to great effect in in her MaddAddam trilogy, in which pigs designed to grow human organs (pigoons) developed humanlike intelligence. Atwood’s imagined future is speculative, but the science is catching up fast.  And as it does, it may become harder to draw the line between humans and humanlike animals.

This isn’t a completely new challenge. Scientists have been creating chimeric animals for some time using cells other than stem cells—for instance, growing human tumors in rodents, to better study them. As far back as 2000, the National Institutes of Health established research guidelines that prohibited combining human stem cells with animal eggs and embryos. In 2009, the agency strengthened those guidelines. However, as scientists began to push the boundaries of chimera research, in September 2015 the agency placed a moratorium on using human stem cells in all nonhuman animals while it worked out what to do.

Following a workshop held late in 2015 and considerable internal deliberation, the agency has now put forward two proposals for public comment. One is an amendment to the 2009 guidelines that would extend slightly what researchers cannot do with nonhuman primates and breeding animals. The other proposal—and the more relevant of the two here—would establish an internal committee that reviews proposals for using human stem cells in nonhuman animals.

Here, NIH is proposing to set up an internal committee that would decide which chimera research proposals get funded and which do not. According to the agency’s announcement, it’s looking for public input on the scope of the committee—essentially what types of research proposals would end up in front of it and how it would subsequently decide what is ethical and responsible (and therefore fundable) and what is not.

Initially, the plan is for the committee to focus on general research using human stem cells in nonhuman vertebrates (excluding primates) and on research where human cells may end up affecting an animal’s brain function. This second point gets to the core of concerns that somehow, by introducing human stem cells, hybrid animals could develop humanlike brain functions, possibly resulting in greater intelligence or more humanlike behavior. The problem is, once introduced to the embryo, it’s not always possible to tell where human stem cells will end up and what they’ll do.

This committee will be made up of NIH staff, presumably including experts in socially responsible research and innovation, as well as stem cell researchers and bioethicists. But beyond the 30-day comment period, it’s unclear how they’ll engage (or even whether they’ll engage) with ordinary people. Yet for ethical and responsible chimera research, ongoing public participation in the review process is essential.  There are too many “should we?” questions that must not be left solely to scientists: What are the ethical boundaries around creating human-nonhuman chimera, for instance? Or how do we decide what are acceptable or unacceptable outcomes?

For this public participation to be meaningful, scientists and others need to do a better job explaining chimera research, what they are planning to do (and why), and what the benefits and consequences might be. They also need to get better at making sure everyone who wants a voice has one, while ensuring that decisions are grounded in reality.  Discouraging input from citizens on ethical discussions is hardly socially responsible behavior—but neither is promoting decisions that fly in the face of evidence.

Yet enabling effective citizen engagement and input is tough, especially as the ideal of public input gives way to the reality of busy lives and convoluted bureaucracies.

One possibility is to augment the internal committee with a federal advisory committee that includes citizen representation, although speaking as an ex-fed, such committees can become a major bureaucratic headache if they’re not well-conceived and run.

An alternative (and less bureaucratically stressful) approach is to support the internal committee with organized input from external experts and citizens. There are various ways this can be done—all with their different strengths and weaknesses. One that’s gaining some traction in the United States, though, is the approach taken by the Expert & Citizen Assessment of Science & Technology network. ECAST brings citizens and experts together around specific topics in an organized setting designed to both inform participating citizens and solicit their input on the issue under consideration. The network’s affiliated with my own school, the School for the Future of Innovation in Society, at Arizona State University, so I must confess to some bias here. (Disclosure: ASU is a partner with Slate and New America in Future Tense.) But it’s developing a track record of successfully informing complex policy decisions through engaging with ordinary people.

There are, of course, other ways that citizens can become engaged in important decisions around science and technology—through organizations like the American Association for the Advancement of Science for instance, or getting involved with “extreme” citizen science initiatives.

But the bottom line here is that, if the NIH truly wants to know what you think about creating human-nonhuman hybrids, it needs more than just 30 days for public comments.

This article is part of Future Tense, a collaboration among Arizona State University, New America, and Slate. Future Tense explores the ways emerging technologies affect society, policy, and culture. To read more, follow us on Twitter and sign up for our weekly newsletter.