Human cloning

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Human cloning is the creation of a genetically identical copy of an existing, or previously existing, human being or clone tissue from that individual. The term is generally used to refer to artificial human cloning; human clones in the form of identical twins are commonplace, with their cloning occurring during the natural process of reproduction.

Although genes are recognized as influencing behavior and cognition, "genetically identical" does not mean altogether identical; identical twins, despite being natural human clones with identical DNA, are separate people, with separate experiences and not altogether overlapping personalities. The relationship between an "original" and a clone is rather like that between identical twins raised apart; they share all the same DNA, but little of the same environment. A lively scientific debate on this topic occurred in the journal Nature in 1997.^[1] 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.)

Contents 1 Techniques 2 Claims of success in human cloning beyond the embryo stage 3 Possible advantages 4 The current law on human cloning 4.1 U.N. 4.2 Australia 4.3 European Union 4.4 U.S. 4.5 U.K. 5 External links 6 References

[edit] Techniques

                                                            The most successful common cloning technique in non-human mammals is the process which allowed for Dolly the sheep. It is also the technique used by ACT, the first company to successfully clone a human embryo (see research section below). An egg cell taken from a donor has its nucleus removed.hghghgh 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.     

In principle, another way of cloning would be by parthenogenesis, where an unfertilized egg cell is induced to divide and grow as if it were fertilized. Even if it were practical with mammals, this technique could work only with males. Discussion of human cloning generally assumes the use of somatic cell nuclear transfer, rather than parthenogenesis. l

[edit] 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, and his claims are 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.

A mother in America plans to pay $500,000 to the Clonaid organization to clone her deceased daughter. In December 2004 Dr. Boisselier, 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.

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 2004 a group of scientists led by Hwang Woo-Suk of Seoul National University in South Korea claimed to have grown 30 cloned human embryos to the one-week stage, and then successfully harvested stem cells from them. The results of their experiment were published in the peer-reviewed journal Science.

On May 30, 2005, Hwang's team announced the creation of 11 lines of human stem cells, using a different technique (Hwang et al. 2005).

[edit] Possible advantages

Many hopes have been put upon human cloning. Therapeutic cloning could provide needed organ transplants. A cure for cancer by a better understanding of the cell-differentiation process, as well as better treatments for heart attacks and improved cosmetic surgery, are being cited as being possible with the new technology. Dr. Richard Seed thinks that human cloning will help us understand, and eventually reverse, the human aging process.

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 families have high hopes for reproductive cloning. How to Build a Human, a documentary by BBC and The Discovery Channel, illustrated the prospects by showing an American family that wants to make a clone of their third child, who, although genetically healthy, had serious mental and physical deficiencies due to complications at birth and is expected to die soon. Other people hope to clone their already deceased children. Jonathan Colvin, a Canadian technical writer, has expressed his desire to clone himself while repairing his genetic defect (cystic fibrosis), thereby creating a version of himself free of the fatal disease.^[2][3]

[edit] The current law on human cloning

[edit] 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, 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 February 2005 a vaguely worded and non-binding United Nations Declaration on Human Cloning was finally adopted.^[4]

[edit] 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.

[edit] 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 European Constitution would, if ratified, make the charter legally binding for the institutions of the European Union.

[edit] 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. President George W. Bush is opposed to human cloning in any form. 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 institution 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.

[edit] U.K.

The British government introduced legislation in order to allow licensed therapeutic but not reproductive cloning in a debate in January 2001 after an amendment to the Human Fertilisty & Embryology Act 1990. However on November 15, 2001 opposition groups won a High Court legal challenge that effectively blocked cloning of embryos for therapeutic purposes. They discovered a loophole which allows reproductive cloning to be performed also. Anti-abortion group say that a new debate is necessary because of recent technologies having been developed that might circumvent the need for embryonic cloning. The government overruled this attempt at the beginning of March 2002 and currently therapeutic cloning is allowed under license of the Human Fertilisation and Embryology Authority. The first known 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.

[edit] External links

• The Reproductive Cloning Network. Cloning articles, resources and links
• Therapeutic and reproductive cloning discussed from personal perspective, Essay by G. Waite, PhD
• "Clone": the history of a euphonious scientific term. Ursula Mittwoch
• Futuristic Approach for Human Cloning/Coping Technology
• "Variations and voids: the regulation of human cloning around the world" academic article by S. Pattinson & T. Caulfield

[edit] References