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Cloning





Cloning is a very controversial theme. It is considered by many people and nations as an immoral practice, a bad appendix of science. Cloning does violate the laws of nature, because we are the ones that manipulate it. It interferes with the natural and common reproduction. But we have to consider another point of view. What will happen to the people who can 't procreate by the traditional way, nature 's way? Don 't they have the same rights with us to become happy, to fulfill their wishes of becoming a father or a mother? How can we stop people from practicing the universal right of searching for happiness? If we do it, we would be selfish. That 's why cloning could be a solution to that dilemma.


We should proceed this debate with the history of cloning. The modern era of laboratory cloning began in 1958 when F.C. Steward cloned carrot plants from mature single cells placed in a nutrient culture containing hormones. The first cloning of animal cells took place in 1964. John B. Gurdon took the nuclei from tadpoles and injected them into unfertilized eggs. The nuclei containing the original parents ' genetic information had been destroyed with ultraviolet light. When the eggs were incubated, Gurdon discovered that only 1% to 2% of the eggs had developed into fertile adult toads. The first successful cloning of mammal was achieved nearly twenty years later. Scientists from Switzerland and the U.S successfully cloned mice using a method similar to Gurdon 's. In 1993 the first human embryos were cloned using a technique that placed individual embryonic cells in a nutrient culture where the cells then divided into 48 new embryos. These fertilized eggs did not develop to a stage that could be used for transplantation into a human uterus.
WHAT IS CLONING?
Cloning is the creation of an organism that is an exact copy of another. There are different types of cloning. A basic understanding of the different types of is the key to taking an informed stance on current public policy issues and making the best personal decisions.

WHAT IS A CLONE?


As per biology, a clone is a cell or an organism that is genetically identical to another cell or organism. Many simple organisms such as bacteria reproduce themselves by copying their DNA and splitting in half. The two bacteria that result from this form of asexual reproduction are genetically similar, they are clones of each other. In contrast, during the process of sexual reproduction, the nucleus of a sperm cell, which carries the father 's DNA, fuses with the nucleus of an egg cell, which contains the mother 's DNA. The resulting offspring carry genetic material from both parents and are not identical to either parent.
The verb ' 'to clone ' ' refers to the process of creating cloned cells or organisms. The process differs, depending on the kinds of cells used in the cloning procedure and the desired result. Usually, when scientists clone an animal, they take the nucleus of a cell (which contains chromosomes made of deoxyribonucleic acid-DNA and proteins) and place it into an egg cell (also called oocyte) from which the nucleus had been removed. The egg cell then divides to produce an embryo that develops into an animal, if the procedures work as planned.

WHAT IS HUMAN CLONING?
A "human clone " is a time-delayed identical twin of another person. A clone is not an exact replica of the original, but just a much younger identical twin. As with identical twins, the clone and the original being will have different set of fingerprints. Ever since Dolly 's (the cloned sheep) birth in 1997 shocked an unexpecting world, Governments have been busy trying to prevent the advent of human cloning.


There is also the fear that someone would create armies of soldiers or even produce large amounts of workers. This could create lower class for clones and compromising individualities.
A "black market " of fetuses could arise from desirable donors that will want to clone themselves, i.e.: athletes, film stars, scientists and others.
Technology is not fully developed. It has a low fertility rate. In cloning Dolly, 277 eggs were used, 30 started to divide, 9 induced pregnancy, and only one survived to term (Nash).
Clones may be treated as second-class citizens. Human cloning would bring grave risks of abuses to human dignity and exploitation by unscrupulous people.
Unknown psychosocial harms with impacts on the family and society. Many see this as a violation of the uniqueness of a human life, which God has given to each of us and to no one else.

WHAT IS CLONING? ARE THERE DIFFERENT TYPES OF CLONING?
When the media report on cloning in the news, they are usually talking about only one type called reproductive cloning. There are different types of cloning however, and cloning technologies can be used for other purposes besides producing the genetic twin of another organism. A basic understanding of the different types of cloning is the key to taking an informed stance on current public policy issues and making the best possible personal decisions. The following three types of cloning will be discussed: (1) recombinant DNA technology or DNA cloning, (2) reproductive cloning, and (3) therapeutic cloning.
(1) Recombinant DNA Technology or DNA Cloning
The terms "recombinant DNA technology ", "DNA cloning ", "molecular cloning " or "gene cloning " all refer to the same process the transfer of DNA fragment of interest from one organism to a self-replicating genetic element such as a bacterial plasmid. The DNA of interest can then be propagated in a foreign host cell. This technology has been around since the 1970s, and it has become a common practice in molecular biology labs today.
Scientists studying a particular gene often use bacterial plasmids to generate multiple copies of the same gene. Plasmids are self-replicating extra-chromosomal circular DNA molecules, distinct from the normal bacterial genome. Plasmids and other types of cloning vectors are used by Human Genome Project researchers to copy genes and other pieces of chromosomes to generate enough identical material for further study.
To "clone a gene " a DNA fragment containing the gene of interest is isolated from chromosomal DNA using restriction enzymes and then united with a plasmid that has been cut with the same restriction enzymes. When the fragment of chromosomal DNA is joined with its cloning vector in the lab it is called a "recombinant DNA molecule ".

Following introduction into suitable host cells the recombinant DNA can then be reduced along with the host cell DNA. Bacteria are most often used as the host cells for recombinant DNA molecules but yeast and mammalian cells are also used.



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