Human-Nonhuman Chimera Research in Canada

Françoise Baylis explains Canada’s regulatory framework for human-nonhuman chimera research and suggests that the proposed changes to the NIH guidelines to permit the funding of such research may have implications for Canadian research.


Last month, the United States National Institutes of Health (NIH) announced proposed changes to its Guidelines on Human Stem Cell Research to permit the funding of some research involving the creation of human-nonhuman chimeras. Chimeras are beings with cells from two or more genetically distinct organisms and these organisms may or may not be from the same species. Specifically, the plan is to permit NIH funding of research involving the transfer of human stem cells or tissues into nonhuman embryos. The proposed changes would end the current moratorium on such research.

With this announcement, the public was invited to comment on the proposed changes.  In response, and in an effort to encourage formal submissions to the NIH, a group of academics working in animal studies published an engaging commentary that can reasonably be read as a call to action by like-minded individuals. In their view, “it is unreasonable for the NIH to end its moratorium on funding human-nonhuman chimera research when so many serious issues clearly remain unaddressed.” They call for further deliberation to “more fully examine the ethical issues and challenges raised by this research.”

For my part, I want to extend the call to action to this side of the border. I believe that the ethical issues and challenges with human-nonhuman chimera research are as acute in Canada as in the United States. Canadians may not be as sensitive to this fact because they may believe that the type of human-nonhuman chimera research described above is legally prohibited in Canada.  This is not the case.  It follows that if the possible creation of nonhuman animals with ‘human-like’ traits is a legitimate worry in the United States, then it is also a legitimate worry in Canada.

In Canada, the Assisted Human Reproduction Act of 2004 stipulates that “No person shall knowingly … create a chimera, or transplant a chimera into either a human being or a non-human life form.”  The legislation defines a chimera as “an embryo into which a cell of any non-human life form has been introduced; or an embryo that consists of cells of more than one embryo, foetus or human being.” This has been interpreted by some as a prohibition on the type of research that the NIH is now looking to fund. Not so.

To properly understand the legal prohibition in Canada, one has to also consult the definition of an embryo included in the Assisted Human Reproduction Act. There an embryo is defined as “a human organism during the first 56 days of its development following fertilization or creation…”.  What this means is that in Canada only one type of part-human chimera research is legally prohibited – namely, research that involves putting nonhuman stem cells into human embryos. This is different from research that involves putting human stem cells into nonhuman embryos which is the research that the NIH now wants to fund. Here, directionality matters.

To understand what is permissible in Canada as regards research involving the transfer of human stem cells into nonhumans one has to consult the Tri-Council Policy Statement: Ethical Conduct for Research Involving Humans. These are the guidelines governing research funded by our federal granting agencies – the Canadian Institutes of Health Research, the Natural Sciences and Engineering Research Council of Canada and the Social Sciences and Humanities Research Council of Canada.

These research guidelines, consistent with the legal prohibition in the Assisted Human Reproduction Act, prohibit research that combines human or nonhuman embryonic stem cells with human embryos. The guidelines also explicitly prohibit “research in which human embryonic stem cells, embryonic germ cells, induced pluripotent stem cells, or other cells that are likely to be pluripotent are combined with a non-human embryo.” They do, however, permit limited chimera research involving the transfer of human stem cells into nonhuman animals, from birth to adulthood provided these ‘humanized’ animals are not used for reproductive purposes. This research is subject to review and approval by the national Stem Cell Oversight Committee and local Research Ethics Boards.

Thus, in Canada, while it is illegal to create human-nonhuman chimeras using human embryos, it is not illegal to do so using nonhuman embryos. It is simply that such chimera research cannot be funded by the three federal granting agencies because of the prohibition in the research guidelines. While the NIH moratorium is in place, the situation in Canada is analogous to that in the United States – in both countries the federal granting agencies cannot fund research involving the transfer of human stem cells or tissues into nonhuman embryos.

In the near future the NIH funding moratorium may be lifted. As a result, there may be pressure to amend the Canadian research guidelines. For this reason, Canadians had best pay close attention to the current debate in the United States.


Françoise Baylis is a Professor and Canada Research Chair in Bioethics and Philosophy at Dalhousie University @FrancoiseBaylis