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Frequently Asked Questions
about Human Cloning and the Council's Report:

"Human Cloning and Human Dignity:
An Ethical Inquiry

1. What is cloning?
Cloning is a form of reproduction in which offspring result not from the chance union of egg and sperm (sexual reproduction) but from the deliberate replication of the genetic makeup of another single individual (asexual reproduction). Human cloning, therefore, is the asexual production of a new human organism that is, at all stages of development, genetically virtually identical to a currently existing or previously existing human being. (Key terms are defined in Chapter 3 of the report.)

2. How is cloning related to somatic cell nuclear transfer?

Somatic cell nuclear transfer (SCNT) is the technique by which cloning is accomplished. It involves introducing the nuclear material of a human somatic cell (donor) into an oocyte (egg cell) whose own nucleus has been removed or inactivated, and then stimulating this new entity to begin dividing and growing, yielding a cloned embryo. (Key terms are defined in Chapter 3 of the report, and a detailed description of SCNT is provided in Chapter 4 of the report.)

3. For what purposes would anyone want to perform human cloning?
Human cloning might be undertaken for two general purposes. One potential use would be to produce children who would be genetically virtually identical to pre-existing individuals. Another would be to produce cloned embryos for research or therapy. For example, a scientist might wish to create a cloned embryo which would then be taken apart to yield embryonic stem cells that could potentially be used in biomedical research or therapies. The Council has termed the first use “cloning-to-produce-children” and the second “cloning-for-biomedical-research.” (The Council’s choice of terms is discussed at length in Chapter 3 of the report.)

4. Why does human cloning matter?
The prospect of cloning-to-produce-children, which would be a radically new form of procreation, raises deep concerns about identity and individuality, the meaning of having children, the difference between procreation and manufacture, and the relationship between the generations. Cloning-for-biomedical-research also raises new questions about the manipulation of some human beings for the benefit of others, the freedom and value of biomedical inquiry, our obligation to heal the sick (and its limits), and the respect and protection owed to nascent human life. Moreover, the legislative debates over human cloning raise questions about the relationship between science and society, especially about whether society can or should exercise ethical and prudential control over biomedical technology and the conduct of biomedical research. Rarely has such a seemingly small innovation raised such large questions.

5. Has anyone tried to perform human cloning?
Yes, though the extent to which attempts have been successful at this stage is unclear. One American company and one American university are known to have attempted to produce cloned human embryos, but at least in early experiments were unsuccessful. Reports from China and elsewhere suggest that serious attempts have been made around the world. At this stage, it is unclear if they have succeeded and to what extent. In addition, researchers at Stanford University have announced their intention to create cloned human embryos for research. Several groups around the world also claim to have to have transferred cloned human embryos in an effort to impregnate women, and at least one group claims such pregnancies have resulted in several births. These claims as of April 2003 have not been substantiated.

6. How many mammalian species have been cloned? With what rates of success?

Attempts have been made to clone at least ten mammalian species, but at this point, published reports suggest that seven species—sheep, cattle, goats, mice, pigs, cats, and rabbits—have been successfully cloned. Rates of success have been quite low: approximately 5 percent of attempts have resulted in live births. Moreover, a substantial number of live-born cloned mammals have shown severe abnormalities after birth. Some surviving cloned cattle, however, do appear physiologically similar to their uncloned counterparts, and at least one cloned sheep (Dolly) and some cloned cows have given birth to offspring. (Scientific details are provided in Chapter 4 of the report.)

7. How is research cloning related to embryonic stem cell research?
Cloning is related to stem cell research in that both procedures deal with human embryos, and the human embryos in both cases are destroyed when their stem cells are extracted.

In cloning-for-biomedical research as well as in embryonic stem cell research, scientists extract cells from embryos in order to use those stem cells for research purposes.

The human embryos used in stem cell research are made in a laboratory by combining sperm and eggs, frequently in an attempt to compensate for infertility. A cloned human embryo does not result from the random union of sperm and egg, but from a process called somatic cell nuclear transfer, in which the nucleus containing DNA from a cell of one individual is put into an egg whose nucleus has been removed. The resulting cloned embryo becomes genetically virtually identical to the individual whose DNA was inserted into the enucleated egg.

(Details are provided in Chapter 4 and 6 of the report.)

8. Why might anyone want to clone a child?
Cloning-to-produce-children might serve several purposes. It might allow infertile couples or others to have genetically related children; permit couples at risk of conceiving a child with a genetic disease to avoid having an afflicted child; allow the bearing of a child who could become an ideal transplant donor for a particular patient in need; enable a parent to keep a living connection with a dead or dying child or spouse; or even to try to “replicate” individuals of great talent or beauty. These purposes have been defended by appeals to the goods of freedom, existence (as opposed to nonexistence), and well-being. (See Chapter 5 of the report.)

9. What are the arguments against cloning a child?
The Council holds that cloning-to-produce-children would violate the principles of the ethics of human research. Given the high rates of morbidity and mortality in the cloning of other mammals, cloning-to-produce-children would be extremely unsafe, and, as such, attempts to produce a cloned child would be highly unethical. Even conducting experiments in an effort to make cloning-to-produce-children safer would itself be an unacceptable violation of the norms of research ethics, so there seems to be no ethical way to try to discover whether cloning-to-produce-children can become safe, now or in the future. Beyond those safety issues, the Council holds that cloning-to-produce-children would be a radically new form of human procreation that leads to concerns about: 1) problems of identity and individuality; 2) concerns regarding manufacture; 3) the prospect of a new eugenics; 4) troubled family relations; and 5) effects on the family. (These are detailed in Chapter 5 of the report.)

10. Why might anyone want to produce cloned embryos for biomedical research?
Some scientists believe that stem cells derived from cloned human embryos, produced explicitly for such research, might prove uniquely useful for studying many genetic diseases and devising novel therapies. (See Chapters 4 and 6 of the report.)

11. Is cloning-for-biomedical-research the only way to treat some diseases?
No one knows. In fact, it is not known if cloning-for-biomedical-research will help treat diseases at all, but some researchers believe they have sound reasons for expecting valuable knowledge from such research. Other avenues of research on diseases are also being pursued, including adult stem cell research and various alternative techniques for dealing with immune rejection. Cloning-for-biomedical-research is one of many potential routes to treatments and cures, but at this point researchers have no way of knowing for sure which route will prove most productive. (See Chapter 6 of the report.)

12. What are the arguments for and against cloning for biomedical research?
The primary argument for proceeding with cloning-for-biomedical-research is that it might lead to advances in medical knowledge and toward treatments and cures. Those members of the Council who support cloning-for-biomedical-research believe that it may offer uniquely useful ways of investigating and possibly treating many chronic debilitating diseases and disabilities, providing aid and relief to millions who are suffering, and to their families and communities. They also believe that the moral objections to this research—some of which are taken quite seriously by some of these members—are outweighed by the great good that may come from it.

The case against proceeding with the research does not deny the possibility (albeit speculative) of medical progress from this work, but rests on the belief of those members of the Council who oppose the research that it is morally wrong to exploit and destroy developing human life, even for good reasons, and that it is unwise to open the door to the many undesirable consequences that are likely to result from this research. These members point to concerns about our obligations to nascent human life; the crossing of an important moral boundary through the creation of human life expressly and exclusively for the purpose of its use in research; and possible further moral harms to our society.

(Both sets of arguments are presented in detail in Chapter 6 of the report.)

13. Is there any connection between the two uses of human cloning?
Both potential uses (cloning-to-produce-children and cloning-for-biomedical-research) begin in the same way with the act of cloning (by somatic cell nuclear transfer) that produces a cloned human embryo. They are therefore connected by technique and separated by intent. Any attempt to limit or regulate one would almost inevitably touch upon the other.

14. What does U.S. law now say about human cloning (state and federal)?
There is currently (as of April 2003), no federal law on cloning, though the issue is being hotly debated in Congress. Because there is so much activity on the state level in this area, we are posting links to websites that track these data on a regular basis. The President's Council on Bioethics makes no claims as to their accuracy and our posting these links should not be construed as an endorsement of their contents.

15. What do other countries do about human cloning?
Many countries have passed laws regarding one or both uses of human cloning. Approaches vary widely from country to country, with some banning both uses of cloning (for instance, Australia, Canada, France, Germany, Italy, and Norway), while others have prohibited cloning-to-produce-children while allowing and in some cases regulating cloning-for-biomedical-research (for instance, the United Kingdom). Several nations have also begun work in the United Nations toward an international treaty banning one or both forms of human cloning.

16. What are the Council’s policy recommendations on human cloning?

A minority of the Council (seven members) recommended a ban on cloning-to-produce-children, with federal regulation of the use of cloned embryos for biomedical research. Such a policy, they argue, would permanently ban cloning-to-produce-children, which nearly all Americans oppose, and would allow potentially important biomedical research to continue, thus offering hope to many who are suffering. These members believe that a regulatory system would be sufficient to protect against abuses and to prevent the implantation of cloned embryos to initiate a pregnancy. Above all, they believe that society should support and affirm the responsible effort to find treatments and cures for those who need them.

A majority of the Council (ten members) recommended a ban on cloning-to-produce-children combined with a four-year moratorium on cloning-for-biomedical-research, and also called for a federal review of current and projected practices of human embryo research, pre-implantation genetic diagnosis, genetic modification of human embryos and gametes, and related matters.

Such a policy, they argue, would most effectively ban cloning-to-produce-children, which nearly all Americans oppose, and would provide time for further democratic deliberation about cloning-for-biomedical research, a subject about which the nation is divided and where there remains great uncertainty.

A moratorium would allow time for moral persuasion; for further animal experiments and progress on alternative avenues of research (including adult stem cells, and other approaches to the immune rejection problem); and for development of possible future regulations by those who do not wish to see the moratorium made permanent.

It would show respect for the views of the large number of Americans who have serious ethical problems with this research, and it would promote a fuller and better-informed public debate. The moratorium, they argue, would also enable society to consider this activity in the larger context of research and technology in the areas of developmental biology, embryo research, and genetics.

Finally, a moratorium, rather than a lasting ban, signals a high regard for the value of biomedical research and an enduring concern for patients and families whose suffering such research may help alleviate. These members believe that on this important subject American society should take the time to make a judgment that is well-informed, respectful of strongly held views, and representative of the priorities and principles of the American people. They believe this proposal offers the best available way to a wise and prudent policy

(Both recommendations, and supporting arguments, are presented at length in Chapter 8 of the report.)

17. Are disagreements over cloning basically a clash of religion and science?

Disagreements over the ethical and policy positions regarding human cloning do not seem to fall along lines of science and religion. The Council’s own deliberations are an example of this. Eight of the Council’s eighteen members have degrees in medicine or biomedical science. Four of these supported the majority proposal, while the other four supported the minority. Meanwhile, members with strong religious convictions can be found on both sides as well. Unusual left-right coalitions have also been seen on both sides of the cloning debate in Congress. Differing assessments of the moral significance of the facts at hand have shaped the differing opinions of the members.

18. Where does President George W. Bush stand on human cloning?
President Bush has expressed strong opposition to all human cloning, whether for biomedical research or for producing children. For more information about his views, visit the White House website at

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