- BIOETHICS FORUM ESSAY
There is another side to the blockbuster announcement last year that researchers have learned how to create stem cells by genetically reprogramming skin cells, turning back their developmental clock so that they acquire the capacity to become almost any type of cell in the body. The news was hailed as sweeping aside the moral objections to research on embryonic stem cells. It also showed that those objections were not what we thought they were.
First, it’s important to see that the new procedure might turn out to be analogous to somatic cell nuclear transfer, commonly just called cloning. In SCNT, researchers remove the nucleus from an egg and insert the nucleus of a fully differentiated cell from the body – often a skin cell. The egg’s cytoplasm then reprograms the nucleus, resulting in what seems to qualify as a new kind of human embryo. To be sure, the new thing differs from the standard kind of embryo in some ways: no sperm is required, and no sexual recombination of genes occurs. For some, this difference has seemed significant enough to warrant a difference in classification; Paul McHugh, a member of the President’s Council on Bioethics, wrote in 2004that SCNT looked more like tissue culture than reproduction, and he suggested that the thing created through SCNT be called a “clonote” to distinguish it from a zygote, the first step in embryonic development.
But there are lumpers and splitters when it comes to scientific classifications, and the lumpers seem to have won out. SCNT still involves eggs, and the resulting entity looks much like a zygote and may well be capable of developing into a baby. At any rate, the process has worked reasonably well for some other species, and as the science advances, it will probably eventually work for humans.
Cloning is now the traditional procedure, odd as that sounds, for reprogramming a cell. In the new technique, a cell can be reprogrammed without the help of the egg’s cytoplasm, just by inserting some new genes. The resulting cells do not look much like embryos, but they can turn into all of the major tissue types of the body and presumably could differentiate into every kind of cell needed to create a person.
No one is yet calling these new entities “embryos.” Possibly a reprogrammed skin cell lacks the capacity to develop the extra-embryonic tissues, such as a placenta, that it would need in order to implant and come to term. Certainly it looks different; it lacks the egg’s massive cytoplasm. Yet it is too early to say definitively that the new entities are not embryos. If reprogramming through cloning creates a new sort of embryo, different from natural human embryos in important ways, then this new kind of reprogramming might prove to be creating yet another new kind of embryo. Traditional cloning shows that sperm are not needed to create an embryo. There may be nothing magical about the egg, either. In principle, an embryo could be created entirely from scratch.
Of course, whether scientists can create embryos from skin cells is a testable proposition. In the research recently announced, some cell lines formed balls that the researchers called “embryoid.” For all we now know, as the science advances, forthcoming research might produce balls that are “embryoid” not only in appearance but also in how they can develop.
But the critics of embryonic stem cell research are unconcerned. Richard Doerflinger, who works at the U.S. Conference of Catholic Bishops and is a leading opponent of embryonic stem cell research, has said of the new research that he sees “no moral problem with it at all.” This is its own blockbuster development. The objection they have lodged against embryonic stem cell research is that it would require the destruction of embryos, which is murder. A reprogrammed skin cell is certainly not the usual kind of embryo, but destroying one may still turn out to be tantamount to the destruction of potential life, and so to count as murder. The only way critics can have no moral problem with the new research is if their concern about cloning is not, in fact, about the destruction of potential life.
But then what is the objection? One possibility is that even though an egg is not needed to create an embryo, the egg itself is morally significant. Here’s the idea that might be at work: A skin cell can be tweaked so that it acquires the potential to become a person, but that potential is artificial and morally unimportant – a product of the laboratory that may also be taken away in the laboratory. The moral identity of a reprogrammed skin cell is still just “skin cell,” not “embryo.” We can buy it and sell it, culture it and destroy it, and no one really cares.
On the other hand, eggs and the embryos produced from them are expected to try to become people. Their potential is natural, not artificial. Further, because eggs and embryos are morally special – witness the concerns people often have about selling them – intervening in their natural development is morally troubling.
This picture makes the objection to cloning comparable to concerns that arise in a range of other debates about what we can do in and to nature – genetic enhancement of children, sports doping, genetic modification of livestock, extirpation of endangered species, and commercial development of places “untrammeled by man,” as the Wilderness Act puts it. These debates have many differences, but they all feature a common concern about alteration of natural affairs and processes.
If this is right, then we need to rethink the debate over traditional cloning. The moral concerns about taking human life are powerful and clear and lead directly to public policy that upholds those concerns. The moral concerns we might have about intervening into the natural processes of human life may still be very deeply felt, but they are extremely complicated and may not lead neatly to public policy. Given the variety of moral views people have about human nature, restricting public funding for stem cell research may not be reasonable.
Gregory E. Kaebnick is editor of the Hastings Center Report.