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Cloning
Cloning is the process of creating an identical copy of something. In
Biology, it collectively refers to processes used to create copies of DNA
fragments (Molecular Cloning), Cells (Cell Cloning), or organisms. The term also
encompasses situations, whereby organisms reproduce asexually, but in common
parlance refers to intentionally created copies of organisms.
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Human cloning
Human cloning is the creation of a genetically identical copy of an existing or
previously existing human. 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. There are
two commonly discussed types of human cloning: therapeutic cloning and
reproductive cloning. Therapeutic cloning involves cloning adult cells for use
in medicine and is an active area of research. Reproductive cloning would
involve making cloned humans. A third type of cloning called replacement cloning
is a theoretical possibility, and would be a combination of therapeutic and
reproductive cloning. Replacement cloning would entail the replacement of an
extensively damaged, failed, or failing body through cloning followed by whole
or partial brain transplant.
The various forms of human cloning are controversial. There have been
numerous demands for all progress in the human cloning field to be halted. Most
scientific, governmental and religious organizations oppose reproductive
cloning. The American Association for the Advancement of Science (AAAS) and
other scientific organizations have made public statements suggesting that human
reproductive cloning be banned until safety issues are resolved. Serious
ethical concerns have been raised by the future possibility of harvesting organs
from clones. Some people have considered the idea of growing organs
separately from a human organism - in doing this, a new organ supply could be
established without the moral implications of harvesting them from humans.
Research is also being done on the idea of growing organs that are biologically
acceptable to the human body inside of other organisms, such as pigs or cows,
then transplanting them to humans, a form of xenotransplantation.
The first human hybrid human clone was created in November 1998, by American
Cell Technologies. It was created from a man's leg cell, and a cow's egg
whose DNA was removed. It was destroyed after 12 days. Since a normal embryo
implants at 14 days, Dr Robert Lanza, ACT's director of tissue engineering, told
the Daily Mail newspaper that the embryo could not be seen as a person before 14
days. While making an embryo, which may have resulted in a complete human had it
been allowed to come to term, according to ACT: "[ACT's] aim was 'therapeutic
cloning' not 'reproductive cloning'"
On 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 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 destroyed.
Ethical issues of cloning
Although the practice of cloning organisms has been widespread for several
thousands of years in the form of horticultural cloning, the recent
technological advancements that have allowed for cloning of animals (and
potentially humans) have been highly controversial. The Catholic Church and many
religious organizations oppose all forms of cloning, on the grounds that life
begins at conception. Conversely, Judaism does not equate life with conception
and, though some question the wisdom of cloning, Orthodox rabbis generally find
no firm reason in Jewish law and ethics to object to cloning. From the
standpoint of classical liberalism, concerns also exist regarding the protection
of the identity of the individual and the right to protect one's genetic
identity.
Gregory Stock is a scientist and outspoken critic against restrictions on
cloning research.[18]
The social implications of an artificial human production scheme were famously
explored in Aldous Huxley's novel Brave New World.
On December 28, 2006, the U.S. Food and Drug Administration (FDA) approved the
consumption of meat and other products from cloned animals. Cloned-animal
products were said to be virtually indistinguishable from the non-cloned
animals. Furthermore, companies would not be required to provide labels
informing the consumer that the meat comes from a cloned animal.
Critics have raised objections to the FDA's approval of cloned-animal products
for human consumption, arguing that the FDA's research was inadequate,
inappropriately limited, and of questionable scientific validity. Several
consumer-advocate groups are working to encourage a tracking program that would
allow consumers to become more aware of cloned-animal products within their
food.
Joseph Mendelson, legal director of the Center for Food Safety, said that cloned
food still should be labeled since safety and ethical issues about it remain
questionable.
Carol Tucker Foreman, director of food policy at the Consumer Federation of
America, stated that FDA does not consider the fact that the results of some
studies revealed that cloned animals have increased rates of mortality and
deformity at birth. |
