To Clone Or Not To Clone Human? - Facts & Infographic
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What is Cloning?
Cloning is the biological and biotechnological process of producing genetically identical organisms asexually. The word 'clone' is derived from the Greek word klon meaning 'twig'. This is because the earliest form of cloning known to mankind is the reproduction of plants from the twigs or stem cuttings. In biotechnology, cloning is the process or the method used to create identical genes or DNA, entire cells, organs and even entire organism using the cells of the original organism.
The American Medical Association (AMA) defines cloning as "the production of genetically identical organisms via somatic cell nuclear transfer. 'Somatic cell nuclear transfer' refers to the process in which the nucleus of a somatic cell of an existing (or previously existing) organism is transferred into an oocyte from which the nucleus has been removed." AMA defines 'Human cloning' as the application of somatic nuclear transfer technology to the creation of a human being that shares all of its nuclear genes with the person donating the implanted nucleus.
Different Types Of Cloning
Though the word cloning is popularly used to denote reproductive cloning, there are other forms of cloning as well -
DNA Cloning or gene cloning is also known as Recombinant DNA technology or molecular cloning. Using this technology, the DNA fragment which is selected for cloning is transferred from the parent organism into a bacterial plasmid. A bacterial plasmid is usually something that can genetically replicate itself. Once such a replication is done the new (cloned) DNA is now propagated in a new host cell.
Reproductive cloning is the process by which an entire animal, with DNA resembling another animal, is created. In reproductive cloning technology, the DNA of a cell is extracted and placed in an egg (after having removed the original nucleus from the egg). This cell is then grown into an embryo and planted into a surrogate mother through artificial insemination. The DNA of the parent and offspring in this case are identical.
Therapeutic cloning is cloning of the human embryo for research purposes. As the cells start to divide in 'cloned' embryos, stem cells start to separate out. Stem cells are the cells that are capable of renewing themselves through cell-division and are used in tissue repair. In therapeutic cloning, these stem cells are harvested by biologists and studied for treating various diseases. One branch of genetic engineering deals with the replacement of diseased organs with cloned organs and their genetic manipulation of cells to combat diseases.
Why Pursue Cloning?
In some points in history, population growth was seen as a good thing. More people meant more security, more labor, and a stronger, more powerful society. But at a certain point, the increase in people began to have negative consequences on humans and the environment.
Gene Therapy -
Gene therapy is widely used to modify faulty genes and incorporate the corrected genes into the host. Genetically Modified Food and Organisms have already started to show immense benefits in case of genetic engineering of food. Resistance of crops and organisms to disease and enhancement of nutritional value are results of gene therapy. In 2008 the US Food and Drug Administration (FDA) declared that meat and milk from cloned animals and GMO foods were safe for consumption. A number of European states have objected to this and the issue of labeling is a pertinent debate.
Species Survival -
Reproductive cloning has immense potential in populating endangered or extinct species. In 2001, Noah, a gaur (a rare species of ox) was cloned to aid conservation of the species. In 2003, a Banteg, another variety of ox was cloned. Other endangered species, which may benefit greatly from cloning, include the giant panda, the African bongo antelope, and the Sumatran tiger.
Human Cloning -
Much of the research about human cloning is centered on the ability of stem cells to produce tissues to be used for medical treatment. The true potential of therapeutic cloning will be realized when entire organs can be produced to assist the prevalent therapies in case of diseases such as cancer or to produce cells and tissues to correct the damage in degenerative diseases such as the Parkinson's or Alzheimer's disease.
This and the possibility of a number of other untold benefits inspire researchers to push the limits of genetic engineering and cloning.
Considering the Risks
Compromised Immune Functions:
One of the greatest disadvantages of reproductive cloning, as cited by researchers is the high expense and uncertainty with regard to the outcome. While only as many as 1%-10% of the attempts produce an offspring clone; the results are often unsatisfactory. Cloned animals have shown highly compromised immune functions and susceptibility to disease. Short lives, high rates of tumor growth and other infections make cloning a risky activity.
Abnormalities and Mutation:
Researchers at the Whitehead Institute for Biomedical Research in Cambridge, Massachusetts, reported in 2002 that about 4% of the cells in cloned animals were abnormal in their functions. The risk of amplification of genetic defects in case of cloning is very high. Among the mammals cloned till date, high incidences of debilitating ailments and conditions such as the "large-offspring syndrome" are found.
The greatest risk presented by human cloning is the unpredictability of the development of intelligence and psychology in the clones. While it will be unfair to treat a human clone any differently from others, there are no clear guidelines to understand the development of skills and intellectual functions such as development of the moral framework in clones.
The Ethical Debate
Cloning has traditionally been a sensitive subject and the matter of many ethical debates.
The religious opposition to cloning is one of the most important considerations. Roman Catholicism, the United Methodist Church, the United Church of Christ, and the World Council of Churches vehemently oppose cloning. According to some Islamic scholars, cloning some body parts is permissible but cloning of entire beings is not. Judaism does not object to cloning; some recent thinkers have recently objected to cloning and genetic engineering. Most objectors consider cloning "unnatural" and an attempt to play God. The Raelian religion, however, supports human cloning and calls it an attempt to achieve immortality.
Doctors and medical professionals the world over believe that human cloning is a violation of bioethics. The American Medical Association (AMA) and the American Association for the Advancement of Science (AAAS) have opposed cloning. The Center for Bioethics and Human Dignity believes that "human stem cell research requiring the destruction of human embryos is objectionable on legal, ethical, and scientific ground"
Human & Animal Rights -
Article 11 of the UNESCO's Universal Declaration on the Human Genome and Human Rights holds that reproductive cloning of human beings is a deep violation of human rights and dignity. Many animal rights groups also vehemently oppose cloning because of the implicit use of techniques to clinically experiment on animals and for the susceptibility of clones to disease and death.
Cloning Laws and Public Policy in the US
In the US there are no federal laws prohibiting human cloning. Thirteen among the fifty states, however, have adopted laws that prohibit reproductive cloning. These states are - Arkansas, California, Connecticut, Iowa, Indiana, Massachusetts, Maryland, Michigan, North Dakota, New Jersey, Rhode Island, South Dakota, and Virginia. Furthermore Arizona, Maryland, and Missouri have prohibited state funding of cloning research and activities. Despite FDA's approval of meat and milk products from cloned animals in 2008, the confidence of consumers in such food has been very low. The Center for Food Safety also believes such a sanction is a risky one. According to a 2005 survey, over 66% people were uncomfortable in consuming cloned animal products making it important to label these foods clearly.
A USUN policy statement on cloning says "The United States supports a global and comprehensive ban on human cloning through somatic cell nuclear transfer, regardless of the purpose for which the human clone is produced. The United States believes that so-called "therapeutic" or "experimental" cloning, which involves the creation and destruction of human embryos, must be part of this global and comprehensive ban. Thus, the Untied States does not support a ban that is limited merely to "reproductive" cloning" The ban on cloning does not, however, include the production of DNA, cells, organs, plants, and animals. In the same statement, the US administration actively endorses the pursuit of adult stem-cell research to explore its medical potential.
|Embryonic Stem Cell Research||Therapeutic Cloning||Reproductive Cloning|
|Czech Republic||Restricted||No Clear Laws||No Clear Laws|
|Egypt||No Clear Laws||Banned||Banned|
|Iran||Permitted||No Clear Laws||No Clear Laws|
|Poland||No Clear Laws||No Clear Laws||Banned|
|Trinidad & Tobago||Banned||Banned||Banned|
|Ukraine||No Clear Laws||No Clear Laws||Banned|
In most of the other countries there are no clear laws but reproductive cloning of humans is generally a banned activity.
- The first known animals to be cloned were northern leopard tadpoles by Robert Briggs and Thomas J King in 1952. This sparked off most of the interest in the possibilities cloning presents.
- In 1963, Chinese researcher Tong Dizhou cloned Carp, the first cloned fish.
- The first mammal to be cloned was a mouse called Masha in 1986. Masha was cloned bySoviet scientists Nikitin, Veprencev, Sviridova, and Chaylakhyan.
- Dolly, became the most famous sheep in the world when in 1996, researchers declared it the first mammal to be cloned from an adult somatic cell. She was cloned at the Roslin Institute, Scotland.
- Millie, Christa, Alexis, Carrel, and Dotcom - identical pigs, cloned in Blacksburg, Virginia in 2000, for harvesting their organs for medical purposes.
- In 2000, a mouflon called Ombretta was successfully cloned by a team of researchers from the University of Teramo, Italy, and the Roslin Institute of Scotland. This experiment went to prove the immense species rescue potential of cloning.
- In 2000, the first genetically modified rhesus monkey, ANDi was born at the Oregon Health Sciences University.
- In 2001, researchers at a Texas laboratory cloned a domestic pet, a cat and produced a kitten called CopyCat or CC. The cloning was funded by Genetic Savings & Clone,
- In 2003, the Haflinger foal, Prometea became the first horse to be cloned and the first cloned animal to be carried to term by its own mother.
- In 2003, Idaho Gem, a cloned mule was produced from the DNA of a champion racing mule called Taz at the University of Idaho.
- In 2004, Little Nicky became the first commercially produced clone. A Texas owner of a Maine Coon cat sponsored the activity to produce the clone of her cat, Nicky, which had died the previous year.
- In 2005, Snuppy was declared the first cloned dog and was produced in South Korea. Snuppy was an Afghan hound cloned at the Seoul National University.
- In 2009, Pyrenean Ibex became the first extinct animal to be cloned in an attempt to revive the species. The clone survived for only about seven minutes, though.
- In 2012, Noorie a pashmina goat was cloned at the Sher-e-Kashmir University of Agriculture Sciences and Technology in Jammu & Kashmir, India.
Influence In Cinema
A number of science fiction movies deal with cloning. Some of the well-known ones are - Jurassic Park, The Lost World, The Sixth Day, The Island, The Godsend, Korn, The Boys From Brazil, Parts: A Clonus Horror, Multiplicty, Star Wars, Stepford Wives, Clones, and Repli-Kate.
Cloning as research may not throw up many questions but the implications are many and require grave consideration. Is genetically modifying organisms and creating clones for therapeutic purposes any different from human cloning? Would the identity of a person who undergoes extensive organ replacement through cloning still remain the same? Are we taking a leap into the unknown with human reproductive cloning? Is cloning ethical?