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Human cloning
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Human cloning is the creation of a genetically identical copy of a human being, human cell, or human tissue.
History
Although the possibility of cloning human beings has been the subject of speculation for much of the twentieth century, scientitists and policy makers began to take the prospect seriously in the 1960s. Nobel Prize winning geneticist Joshua Lederberg advocated for cloning and genetic engineering in a seminal article in the American Naturalist in 1966 and again, the following year, in the Washington Post.
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Encyclopedia
Human cloning is the creation of a genetically identical copy of a human being, human cell, or human tissue.
History
Although the possibility of cloning human beings has been the subject of speculation for much of the twentieth century, scientitists and policy makers began to take the prospect seriously in the 1960s. Nobel Prize winning geneticist Joshua Lederberg advocated for cloning and genetic engineering in a seminal article in the American Naturalist in 1966 and again, the following year, in the Washington Post. He sparked a debate with conservative bioethicist Leon Kass, who wrote at the time that "the programmed reproduction of man will, in fact, dehumanize him." Another Nobel Laureate, James Watson, publicized the potential and the perils of cloning in his Atlantic Monthly essay, "Moving Toward the Clonal Man," in 1971.
Human cloning also gained a foothold in popular culture, starting in the 1970s. Alvin Toffler's Future Shock, David Rorvik's In His Image: Toward Cloning of a Man, Woody Allen's film "Sleeper" and the The Boys from Brazil all helped to make the general public aware of the ethical issues surrounding human cloning.
Ethical implications
The cloning of human beings is highly controversial.
Advocates of human therapeutic cloning believe the practice could provide genetically identical cells for regenerative medicine, and tissues and organs for transplantation. Such cells, tissues, and organs would neither trigger an immune response nor require the use of immunosuppressive drugs. Both basic research and therapeutic development for serious diseases such as cancer, heart disease, and diabetes, as well as improvements in burn treatment and reconstructive and cosmetic surgery, are areas that might benefit from such new technology. New York University bioethicist Jacob M. Appel has argued that "children cloned for therapeutic purposes" such as "to donate bone marrow to a sibling with leukemia" might someday be viewed as heroes.
Proponents claim that human reproductive cloning also would produce benefits. Severino Antinori and Panos Zavos hope to create a fertility treatment that allows parents who are both infertile to have children with at least some of their DNA in their offspring.
Some scientists, including Dr. Richard Seed, suggest that human cloning might obviate the human aging process. How this might work is not entirely clear since the brain or identity would have to be transferred to a cloned body. Dr. Preston Estep has suggested the terms "replacement cloning" to describe the generation of a clone of a previously living person, and "persistence cloning" to descregligible SENS (Strategies for Engineered Negligible Senescence) one of the considered options to repair the cell depletion related to cellular senescence is to grow replacement tissues from stem cells harvested from a cloned embryo.
Opponents of human cloning argue that the process will likely lead to severely disabled children. For example, bioethicist Thomas Murray of the Hastings Center argues that "it is absolutely inevitable that groups are going to try to clone a human being. But they are going to create a lot of dead and dying babies along the way."
Techniques
There are, as of December 2008, no documented cases of a living human being produced through human cloning. However, the most successful (though inefficent) common cloning technique in non-human mammals is the process by which Dolly the sheep was produced. It is also the technique used by Advanced Cell Technology (ACT), the first company to successfully clone early human embryos that stopped at the six cell stage. The process is as follows: an egg cell taken from a donor has its cytoplasm removed. Another cell with the genetic material to be cloned is fused with the original egg cell, transferring its cell nucleus to the enucleated donor egg. In theory, this process, known as somatic cell nuclear transfer, could be applied to human beings.
ACT also reported its attempts to clone stem cell lines by parthenogenesis, where an unfertilized egg cell is induced to divide and grow as if it were fertilized, but only incomplete blastocysts resulted. Even if it were practical with mammals, this technique could work only with females. Discussion of human cloning generally assumes the use of somatic cell nuclear transfer, rather than parthenogenesis.
In January, 2008, Wood and Andrew French, Stemagen's chief scientific officer in California, announced that they successsfully created the first 5 mature human embryos using DNA from adult skin cells, aiming to provide a less-controversial source of viable embryonic stem cells. Dr. Samuel Wood and a colleague donated skin cells, and DNA from those cells was transferred to human eggs. It is not clear if the embryos produced would have been capable of further development, but Dr. Wood stated that if that were possible, using the technology for reproductive cloning would be both unethical and illegal. The 5 cloned embryos, created in Stemagen Corporation lab, in La Jolla, were later destroyed.
Claims of success in human cloning beyond the embryo stage
In 1978 David Rorvik claimed in his book In his Image: The Cloning of a Man that he had personal knowledge of the creation of a human clone. A court case followed. He failed to produce corroborating evidence to back up his claims; now regarded as a hoax.
Severino Antinori made claims in November, 2002 that a project to clone human beings had succeeded, with the first human clone due to be born in January 2003. His claims were received with skepticism from many observers.
In December 2002, Clonaid, the medical arm of a religion called Raëlism, who believe that aliens introduced human life on Earth, claimed to have successfully cloned a human being. They claim that aliens taught them how to perform cloning, even though the company has no record of having successfully cloned any previous animal. A spokesperson said an independent agency would prove that the baby, named Evá, is in fact an exact copy of her mother. Shortly thereafter, the testing was cancelled, with the spokesperson claiming the decision would ultimately be left up to Evá's parents.
On October 9, 2003, newspaper Le journal de Montréal published an article accusing Clonaid and the Raelian religion of maintaining an outright hoax in its claims regarding cloning a human baby.
In December 2004 Dr. Brigitte Boisselier, Clonaid's Chief Executive, claimed in a letter to the UN that Clonaid has successfully cloned 13 children, however their identities cannot be revealed to the public in order to protect them.
The current law on human cloning
U.N.
On December 12, 2001 the United Nations General Assembly began elaborating an international convention against the reproductive cloning of human beings. Lawrence S. B. Goldstein, college professor of cellular and molecular medicine at the University of California at San Diego, claims that the United States, unable to pass a national law, forced Costa Rica to start this debate in the UN over the international cloning ban. Unable to reach a consensus on a binding convention, in March 2005 a non-binding United Nations Declaration on Human Cloning was finally adopted.
Australia
Australia had prohibited human cloning, though as of December 2006, a bill legalising therapeutic cloning and the creation of human embryos for stem cell research passed the House of Representatives. Within certain regulatory limits, and subject to the effect of state legislation, therapeutic cloning is now legal in some parts of Australia.
European Union
The European Convention on Human Rights and Biomedicine prohibits human cloning in one of its additional protocols, but this protocol has been ratified only by Greece, Spain and Portugal. The Charter of Fundamental Rights of the European Union explicitly prohibits reproductive human cloning, though the Charter currently carries no legal standing. The proposed Treaty of Lisbon would, if ratified, make the charter legally binding for the institutions of the European Union.
U.S.
In 1998, 2001, 2004 and 2007 the U.S. House of Representatives voted whether to ban all human cloning, both reproductive and therapeutic. Each time, divisions in the Senate over therapeutic cloning prevented either competing proposal (a ban on both forms or reproductive cloning only) from passing. Some American states ban both forms of cloning, while some others outlaw only reproductive cloning.
Current regulations prohibit federal funding for research into human cloning, which effectively prevents such research from occurring in public institutions and private institutions such as universities which receive federal funding. However, there are currently no federal laws in the United States which ban cloning completely, and any such laws would raise difficult Constitutional questions similar to the issues raised by abortion.
U.K.
The British government introduced legislation in order to allow licensed therapeutic cloning in a debate in January 14, 2001 in an amendment to the Human Fertilization and Embryology Act 1990. However on November 15, 2001 a pro-life group won a High Court legal challenge that effectively left cloning unregulated in the UK. Their hope was that Parliament would fill this gap by passing prohibitive legislation. The government was quick to pass legislation prohibiting reproductive cloning Human Reproductive Cloning Act 2001. The remaining gap with regard to therapeutic cloning was closed when the appeals courts reversed the previous decision of the High Court.
The first licence was granted on August 11, 2004 to researchers at the University of Newcastle to allow them to investigate treatments for diabetes, Parkinson's disease and Alzheimer's disease.
In popular culture
Cloning is a recurring theme in contemporary science fiction. Examples include the novels Joshua Son of None (about the cloning of an assassinated U.S. president strongly implied to be John F. Kennedy) and The Boys from Brazil (cloning Adolf Hitler), as well as the Star Wars movies and TV series The Clone Wars. The 2000 Arnold Schwarzenegger film The 6th Day and 2005 The Island directed by Michael Bay also explores the theme of human cloning.
Religious objections
The Roman Catholic Church, under the papacy of Benedict XVI, has condemned the practice of human cloning, in the magisterial instruction Dignitas Personae, stating that it represents a grave offense to the dignity of that person as well as to the fundamental equality of all people. .
External links
- academic article by S. Pattinson & T. Caulfield
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