The Magazine

Defending Life and Dignity

How, finally, to ban human cloning.

Feb 25, 2008, Vol. 13, No. 23 • By LEON R. KASS
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Here is what's new. After the 2005 Korean reports of the cloning of human embryos turned out to be a fraud, many said that human cloning could not be achieved. Yet late in 2007 Oregon scientists succeeded for the first time in cloning primate embryos and growing them to the blastocyst (5-7-day) stage, and then deriving embryonic stem cells from them. More recently, other American scientists, using the Oregon technique, have reported the creation of cloned human embryos. The age of human cloning is here, and the first clones, alas, do not read "made in China."

On the stem cell front, the news is decidedly better. In the last two years, several laboratories have devised methods of obtaining pluripotent human stem cells (the functional equivalent of embryonic stem cells) without the need to destroy embryos. The most remarkable and most promising of these approaches was reported last November by both Japanese and American scientists (including Jamie Thompson, the discoverer of human embryonic stem cells). It is the formation of human (induced) pluripotent stem cells (iPSCs) by means of the reprogramming (also called de-differentiation) of somatic cells. Mature, specialized skin cells have been induced to revert to the pluripotent condition of their originating progenitor.

The therapeutic usefulness of this approach has also been newly demonstrated, by the successful treatment of sickle cell anemia in mice. Some iPSCs were derived from skin cells of an afflicted mouse; the sickle cell genetic defect in these iPSCs was corrected; the treated iPSCs were converted into blood-forming stem cells; and the now-normal blood-forming stem cells were transferred back into the afflicted mouse, curing the disease.

Scientists have hailed these results. All parties to the stem cell debates have noted that the embryonic-stem-cell war may soon be over, inasmuch as science has found a morally unproblematic way to obtain the desired pluri-potent cells. But few people have seen the implications of these developments for the cloning debate: Cloning for the purpose of biomedical research has lost its chief scientific raison d'être. Reprogramming of adult cells provides personalized, rejection-proof stem cells, of known genetic make-up, directly from adults, and more efficiently than would cloning. No need for human eggs, no need to create and destroy cloned embryos, no need for the inefficient process of deriving stem cell colonies from cloned blastocysts. Ian Wilmut himself, the British scientist who cloned Dolly the sheep, has abandoned his research on cloning human embryos to work with reprogrammed adult cells.

Another effect of this breakthrough is that the value for stem cell research of the spare embryos that have accumulated in IVF clinics has diminished considerably, defusing the issue of the ban on federal funding of such research. Why work to derive new stem cell lines from frozen embryos (of unknown quality and unknown genetic composition, and with limited therapeutic potential owing to transplant immunity issues) when one can work with iPSCs to perfect the reprogramming approach and avoid all these difficulties?

That's not the only way the new scientific landscape changes the policy and legislative pictures. We are now able to disentangle and independently advance all three of the goods we care about. First, it now makes great sense to beef up federal support for regenerative medicine, prominently featuring ramped-up work with iPSCs (and other non-embryo-destroying sources of pluripotent human stem cells). The timing is perfect. The promise is great. The potential medical payoff is enormous. And the force of example for future public policy is clear: If we exercise both our scientific wit and our moral judgment, we can make biomedical progress, within moral boundaries, in ways that all citizens can happily support.

Second, we should call for a legislative ban on all attempts to conceive a child save by the union of egg and sperm (both taken from adults). This would ban human cloning to produce children, but also other egregious forms of baby making that would deny children a link to two biological parents, one male and one female, both adults. This approach differs from both the Kennedy-Feinstein-Hatch and the Brownback-Landrieu bills, yet it could--and should--gain support from people previously on both sides. It pointedly neither endorses nor restricts creating cloned embryos for research: Cloning embryos for research is no longer of such interest to scientists; therefore, it is also no longer, as a practical matter, so important to the pro-life cause. Moreover, the prohibited deed, operationally, should be the very act of creating the conceptus (with intent to transfer it to a woman for pregnancy), not, as the Kennedy-Feinstein-Hatch bill would have it, the transfer of the proscribed conceptus to the woman, a ban that would have made it a federal offense not to destroy the newly created cloned human embryos. The ban proposed here thus deserves the support of all, regardless of their position on embryo research.

Third, the time is also ripe for a separate bill to defend nascent life, by setting up a reasonable boundary in the realm of embryo research. We should call for a (four- or five-year) moratorium on all de novo creation--by whatever means--of human embryos for use in research. This would block the creation of embryos for research not only by cloning (or SCNT), the goal of the Brownback-Landrieu anti-cloning bill, but also by IVF. Such a prohibition can now be defended on practical as well as moral grounds. Many human embryonic stem cell lines exist and are being used in research; 21 such lines, still viable, are available for federally funded research, while an even greater number are being studied using private funds. The new iPSC research, however, suggests that our society can medically afford, at least for the time being, to put aside further creation of new human life merely to serve as a natural resource and research tool. We can now prudently shift the burden of proof to those who say such exploitative and destructive practices are absolutely necessary to seek cures for disease, and we can require more than vague promises and strident claims as grounds for overturning the moratorium.

Morally and strategically speaking, this triple-pronged approach has much to recommend it. It is at once more principled, more ambitious, and more likely to succeed than its predecessors. By addressing separately the cloning and embryo-research issues, we can fight each battle exactly on the principle involved: defense of human procreation or defense of human life. By broadening the first ban to include more than cloning, we can erect a barrier against all practices that would deny children born with the aid of reproductive technologies the ties enjoyed by children conceived naturally. By extending the second ban to cover all creation of life solely as an experimental tool, we can protect more than merely embryos created by cloning. We would force everyone to vote on the clear principles involved: Legislators would have to vote yea or nay on both weird forms of baby-making and the creation of human life solely for research, without bamboozling anyone with terminological sleights of hand. And by combining these legislative restrictions with strong funding initiatives for regenerative medicine, we can show the American people and the world that it is possible to vigorously pursue the cures all dearly want without sacrificing the humanity we rightly cherish.

Politically as well, this triple-pronged approach is a winner for all sides. Because the latest science has made creating embryos for research unnecessary and inefficient by comparison with reprogramming, we have the chance to put stem cell science on a footing that all citizens can endorse. Indeed, in return for accepting a moratorium on a scientific approach that is not very useful (creation of new embryos for research), scientists could exact large sums in public support for an exciting area of science. With pro-lifers as their biggest allies, they could obtain the research dollars they need--and their supposed enemies would write the biggest checks. Meanwhile, at the very time the latest science has made affronts to human procreation--cloning, but not only cloning--more likely and even imminent, pro-lifers and scientists can come together to ban these practices in America, as they have already been banned in the rest of the civilized world, without implicating the research debate at all.

In an election year, Congress will be little moved to act quickly on these seemingly low priority items. Moreover, the partisans who have produced the current impasse may still prefer to keep things at stalemate, the better to rally their constituents against the other side. But we can ill afford to be complacent. The science is moving very rapidly. Before the end of the summer, we may well hear of the cloning of primate babies or perhaps even of a human child. Now is the time for action, before it is too late.

Leon R. Kass is Hertog Fellow at the American Enterprise Institute, Harding Professor of Social Thought at the University of Chicago, and former chairman of the President's Council on Bioethics. He speaks here only for himself.