It also suggested that there be a voluntary moratorium in the private sector and that the federal government cooperate with other nations and international organizations to enforce any common aspects of their policies on human reproductive cloning. The NBAC also recommended federal legislation to prohibit human reproductive cloning. Those who desire to carry out reproductive cloning in humans, however, are not planning to use federal funds.
Voluntary moratoriums have been proposed by various industrial and professional associations, such as the Federation of American Societies for Experimental Biology [ 30 ], the American Medical Association [ 31 ; 32 ], the Association of American Medical Colleges [ 31 ] and the American Society for Reproductive Medicine [ 33 ]. A number of bills that would regulate human reproductive cloning have been introduced in Congress.
In general, they are in two categories. The first set of bills would ban both human reproductive cloning and nuclear transplantation to produce stem cells. The second set would ban only human reproductive cloning. While the present report was being developed, a bill introduced by Representative Dave Weldon was passed by the House of Representatives. It would outlaw, with criminal penalties, the production of a reproductively-cloned human embryo and would also outlaw nuclear transplantation to produce human embryonic stem cell lines.
It would also prohibit the importation of any medical treatments from abroad that were created from such activity.
Alternatives to that bill, such as the bill of Representative James Greenwood, would ban human reproductive cloning but would permit the use of nuclear transplantation to produce stem cells; the House defeated an amendment to the Weldon bill proposing this alternative. Similar bills are under discussion in the Senate [ 20 ]. Legislation has been proposed in Illinois,.
Massachusetts, and New York. A number of states including California and New York have laws that apply the federal research regulations to research with human beings conducted within the state that is not otherwise covered by the federal rules because it is not sponsored by a federal agency. Most state laws have difficulties with respect to implementation. For example, if a cow egg were used instead of a human egg, the California law would not apply [ 35 ].
A blanket ban on nuclear transplantation could have unintended consequences, such as an inability to use the process for preimplantation genetic diagnosis or the treatment of some mitochondrial diseases.
Several other countries have instituted human reproductive cloning bans. Germany and the United Kingdom have not signed the protocol, because they are not signatories to the underlying Bioethics Convention. Germany forbids all research on human embryos. In the United Kingdom, human reproductive cloning is now banned by law, but nuclear. The Council of Europe is an intergovernmental organization focused on human rights and other issues.
The Council of Europe should not be confused with the European Union. The two organizations are quite distinct. The 15 European states, however, are all members of the Council of Europe. A voluntary moratorium has worked in the past to delay scientific research. The moratorium leading up to a meeting at Asilomar, California, in successfully delayed recombinant-DNA research until proper guidelines could be put into place [ 38 - 44 ].
The moratorium was conceived by the molecular biology community and imposed on itself, and it was eventually supplanted by a federally sanctioned set of guidelines and a prospective group review process [ 28 ].
The moratorium and guidelines succeeded in part for two reasons that do not pertain to human reproductive cloning today. First, there was a strong consensus on the value of observing the moratorium among the practicing scientists most capable of doing the work, both in the United States and elsewhere.
Second, when the Recombinant DNA Advisory Committee was established and its guidelines put into place, the vast majority of research biologists in the United States were funded by NIH or the National Science Foundation, so the sanction—loss of federal grants—was a strong disincentive. A voluntary moratorium is unlikely to work for human reproductive cloning, because reproductive technology is widely accessible in numerous private fertility clinics that are not subject to federal research regulations.
Several groups have already signaled their intention to forge ahead despite scientific consensus that the techniques are not ready for human application. A number of legal scholars believe that a ban on human reproductive cloning would not be considered constitutional in that it might contravene both a right of privacy specifically, a perceived right to procreative liberty [ 45 ; 46 ] and a right of scientific inquiry.
In addition, it is possible. At this time however, there is no reason to expect that the Supreme Court will expand the right to privacy to include human reproductive cloning.
The Supreme Court has not considered whether ART procedures—particularly an asexual procedure, such as reproductive cloning—are accorded the same considerations. Some, however, do not believe that human reproductive cloning should be treated in the same way as other ART procedures with regard to reproductive rights, because it departs too much from sexual reproduction.
Difficulty in assigning parentage might, for example, be a competing state interest in relation to the national authority promoting a right of privacy [ 48 ]. In the case of a right of scientific inquiry, scientific research is viewed as a means of exercising free speech. This right, although implicit in many Supreme Court cases, has never been explicitly defined [ 49 ].
The existence of state and federal restrictions on research with human subjects suggests that there is a difference between research that poses no threat to others and research that may harm human beings or other important interests. Those who wish to undertake human reproductive cloning lack the fundamental biological knowledge, demonstration of safety in animals, and testing methods to make it a safe course of action. If human reproductive cloning is ever to be undertaken responsibly, it would need to be done systematically with the intention of creating reliable knowledge.
Any responsible efforts toward human reproductive cloning would therefore conform to the federal definition of research. As such, whether the source of funding is public or private, the research would be subject to a review by a review board independent of the investigators conducting the research, such as the Institutional Review Board. Those who wish to reproductively clone humans are more interested in being the first to be successful with human cloning than in collecting reliable knowledge.
Any future attempt at human reproductive cloning would constitute human-subjects research. As such, it would best be regulated according to the following conditions:. The review process would be applied equally to both public- and private-sector research.
The review process would be made open to the public. That would not be the case if review were restricted to FDA unless FDA took special measures, such as those recently taken to make data relevant to the safety of gene-transfer trials and transplantation of animal organs public.
The review process would 1 decide the criteria that should be used to judge whether protocols are ready for human experimentation that is, set the rules and 2 review the protocols involving human experiments to see that they satisfy these criteria that is, apply the rules. Those two functions could be carried out by a single body or by two distinct bodies.
The review process would have to take into account ethical issues beyond clinical safety and efficacy see, for example, the NBAC report [ 29 ].
New legislation or executive action would be required to set up a review system so that it would cover both public and private sectors and be open to the public. A voluntary ban or moratorium is unlikely to work, given that reproductive technology is widely accessible in numerous private fertility clinics that are not subject to federal research regulations.
A ban enforced by legislation would probably need to carry substantial civil or criminal penalties to have an impact on such activities within the United States. If a ban on research in human reproductive cloning is reassessed, participants in any such research efforts would need to be afforded human-subjects protection as described in the Nuremberg and Helsinki codes, US law, and the IOM report Preserving Public Trust: Accreditation and Human Participant Protection Programs [ 15 ].
Such protections include external technical and ethical review by review boards to ensure that proposed experiments are technically and ethically sound. The review boards should be independent of the investigators conducting the research. Cloning in reproductive medicine. National Academy of Sciences, Washington, D. Online at: www. Human therapeutic cloning: Indications, ethics, and other considerations.
Reproductive cloning in humans. Expert witness. Human cloning. House of Representatives, Committee on Energy and Commerce. Subcommittee on Oversight and Investigations.
Mammalian cloning: advances and limitations. Nat Rev Genet Dec, 1 3 The cloning cycle: From amphibia to mammals and back. Reprod Med Rev , 9 1 Hum Mol Genet Aug 15, 10 17 Assisted reproductive technologies. Scientific issues underlying cloning: Epigenetics. Large offspring effects in cattle.
The genetic revolution in artificial reproduction: A view of the future. Hum Reprod Dec, 15 Suppl 5 : Placental defects in nuclear transfer cloned animals. Application of animal cloning data to human cloning. Regulation of cloning. National Academy of Sciences, Washington D. Report of the Institute of Medicine.
National Academy Press. Infertility: Medical and Social Choices. Report of the Office of Technology Assessment. Washington DC: United States. Government Printing Office. ART into science: Regulation of fertility techniques. Science Jul 31, House votes broad ban on cloning: Bill is early blow to stem cell research. Washington Post. Is there a right to clone? Constitutional challenges to bans on human cloning. Harv JL Tech ,. Human cloning: Is the reach of FDA authority too far a stretch? Seton Hall Law Rev , 30 Proposed approach to regulation of cellular and tissue-based products.
The Food and Drug Administration. J Hematother Jun, 6 3 Since then, scientists have cloned cows, cats, deer, horses, and rabbits. They still have not cloned a human, though. In part, this is because it is difficult to produce a viable clone. In each attempt, there can be genetic mistakes that prevent the clone from surviving. It took scientists attempts to get Dolly right. There are also ethical concerns about cloning a human being. Researchers can use clones in many ways. An embryo made by cloning can be turned into a stem cell factory.
Stem cells are an early form of cells that can grow into many different types of cells and tissues. Scientists can turn them into nerve cells to fix a damaged spinal cord or insulin-making cells to treat diabetes. The cloning of animals has been used in a number of different applications. Animals have been cloned to have gene mutations that help scientists study diseases that develop in the animals.
Livestock like cows and pigs have been cloned to produce more milk or meat. In , a cat named CC was the first pet to be created through cloning. Cloning might one day bring back extinct species like the woolly mammoth or giant panda. The audio, illustrations, photos, and videos are credited beneath the media asset, except for promotional images, which generally link to another page that contains the media credit.
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Text on this page is printable and can be used according to our Terms of Service. It was not until , however, that researchers succeeded in cloning the first mammal from a mature somatic cell taken from an adult animal.
After attempts, Scottish researchers finally produced Dolly, the lamb from the udder cell of a 6-year-old sheep. Two years later, researchers in Japan cloned eight calves from a single cow, but only four survived. Besides cattle and sheep, other mammals that have been cloned from somatic cells include: cat, deer, dog, horse, mule, ox, rabbit and rat.
In addition, a rhesus monkey has been cloned by embryo splitting. Despite several highly publicized claims, human cloning still appears to be fiction.
There currently is no solid scientific evidence that anyone has cloned human embryos. In , scientists in South Korea claimed to have successfully cloned a human embryo, but said the experiment was interrupted very early when the clone was just a group of four cells. In , Clonaid, part of a religious group that believes humans were created by extraterrestrials, held a news conference to announce the birth of what it claimed to be the first cloned human, a girl named Eve.
However, despite repeated requests by the research community and the news media, Clonaid never provided any evidence to confirm the existence of this clone or the other 12 human clones it purportedly created. In , a group led by Woo-Suk Hwang of Seoul National University in South Korea published a paper in the journal Science in which it claimed to have created a cloned human embryo in a test tube. However, an independent scientific committee later found no proof to support the claim and, in January , Science announced that Hwang's paper had been retracted.
From a technical perspective, cloning humans and other primates is more difficult than in other mammals. One reason is that two proteins essential to cell division, known as spindle proteins, are located very close to the chromosomes in primate eggs.
Consequently, removal of the egg's nucleus to make room for the donor nucleus also removes the spindle proteins, interfering with cell division. In other mammals, such as cats, rabbits and mice, the two spindle proteins are spread throughout the egg.
So, removal of the egg's nucleus does not result in loss of spindle proteins. In addition, some dyes and the ultraviolet light used to remove the egg's nucleus can damage the primate cell and prevent it from growing. Clones do not always look identical.
Although clones share the same genetic material, the environment also plays a big role in how an organism turns out. For example, the first cat to be cloned, named Cc, is a female calico cat that looks very different from her mother.
The explanation for the difference is that the color and pattern of the coats of cats cannot be attributed exclusively to genes. A biological phenomenon involving inactivation of the X chromosome See sex chromosome in every cell of the female cat which has two X chromosomes determines which coat color genes are switched off and which are switched on.
The distribution of X inactivation, which seems to occur randomly, determines the appearance of the cat's coat. Reproductive cloning may enable researchers to make copies of animals with the potential benefits for the fields of medicine and agriculture.
For instance, the same Scottish researchers who cloned Dolly have cloned other sheep that have been genetically modified to produce milk that contains a human protein essential for blood clotting.
The hope is that someday this protein can be purified from the milk and given to humans whose blood does not clot properly. Another possible use of cloned animals is for testing new drugs and treatment strategies.
The great advantage of using cloned animals for drug testing is that they are all genetically identical, which means their responses to the drugs should be uniform rather than variable as seen in animals with different genetic make-ups. After consulting with many independent scientists and experts in cloning, the U. Food and Drug Administration FDA decided in January that meat and milk from cloned animals, such as cattle, pigs and goats, are as safe as those from non-cloned animals.
The FDA action means that researchers are now free to using cloning methods to make copies of animals with desirable agricultural traits, such as high milk production or lean meat.
However, because cloning is still very expensive, it will likely take many years until food products from cloned animals actually appear in supermarkets. Another application is to create clones to build populations of endangered, or possibly even extinct, species of animals. In , researchers produced the first clone of an endangered species: a type of Asian ox known as a guar. Sadly, the baby guar, which had developed inside a surrogate cow mother, died just a few days after its birth.
In , another endangered type of ox, called the Banteg, was successfully cloned. Soon after, three African wildcats were cloned using frozen embryos as a source of DNA.
Although some experts think cloning can save many species that would otherwise disappear, others argue that cloning produces a population of genetically identical individuals that lack the genetic variability necessary for species survival. Some people also have expressed interest in having their deceased pets cloned in the hope of getting a similar animal to replace the dead one.
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