Everything about Human Cloning totally explained
Human cloning is the creation of a
genetically identical copy of a
human being, human
cell, or human
tissue. The term is generally used to refer to
artificial human cloning, although human clones in the form of
identical twins are commonplace, with their cloning part of the natural process of reproduction.
Although genes influence
behavior and
cognition, "genetically identical" does
not mean altogether identical; identical
twins, despite being natural human clones with nearly identical
DNA, are separate people, with separate experiences and personalities. The relationship between an "original" and a clone is rather like that between identical triplets raised apart; they share nearly all of the same
DNA, but little of the same environment. A lively scientific debate on this topic occurred in the journal
Nature in 1997.
Ultimately, the question of how similar an original and a clone would be boils down to how much of personality is determined by genetics, an area still under active scientific investigation. (See
nature versus nurture and
cloning.)
Techniques
There are no documented cases of successful human cloning. However, the most successful common cloning technique in non-human mammals is the process by which
Dolly the sheep was produced. Dolly was one of 277 attempts. 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. 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 successfully 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 isn't 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
David Rorvik claimed in his book
In His Image: The Cloning of a Man that he'd 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
(External Link
) to the UN that Clonaid has successfully cloned 13 children, however their identities can't be revealed to the public in order to protect them.
Possible advantages
Human cloning might produce many benefits. Human
therapeutic cloning 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.
Human
reproductive cloning also would produce benefits. Antinori and 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 isn't 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 describe the production of a cloned body for the purpose of obviating aging, although he maintains that such procedures currently should be considered science fiction.
In Aubrey de Gray's proposed
SENS (Strategy 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.
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 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, and 2003 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 14th, 2001 after an amendment to the Human Fertilisation and Embryology Act 1990. However on November 15, 2001 a prolife 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. Currently therapeutic cloning is allowed under license from the Human Fertilisation and Embryology Authority. 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.
Further Information
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