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Cloning Essay Research Paper Clones Clones Cloning

Cloning Essay, Research Paper

Clones Clones

Cloning, the process of creating a copy of a plant or animal that is genetically identical to the original through asexual means, has sparked some interesting moral and ethical debate. For years, cloning has been used to produce a greater number of a specific type of plant, such as the Macintosh apple trees, which have all been derived from single mutated plant . Now, however, upon the discovery of a method to clone animals, even humans, people are beginning to become aware of the benefits and consequences of cloning, as well as the ethics involved.

Cloning has had a fairly long history. In 1952, the first successful cloning experiment took place. Scientists Robert Briggs and Thomas King successfully removed the nucleus from a frog egg and replaced it with the nucleus of an undifferentiated cell from another frog. The egg, then placed in a nutrient solution, eventually developed into a healthy tadpole. In 1962, ten years later, a similar experiment took a differentiated intestinal cell and allowed the tadpole created to develop into a healthy, fertile toad. Later, in 1981, a scientist from Cambridge University then combined two embryos, one of a sheep and the other of a goat, making the first ?mosaic? animal ever artificially created?the ?geep,? with the body of a goat covered with patches of sheep?s wool. Then 1984, the first cloned mammals were produced from embryonic nuclei transplanted into unfertilized sheep eggs. Soon after, cloned calves and rabbits, both from embryonic nuclei, and just recently, the first mammal cloned from a fully differentiated adult sheep cell was created.

The process of cloning an animal, especially a mammal, is not an easy one. In fact, there are multiple ways to go about accomplishing the task, depending on the source of the DNA used for cloning. If a differentiated cell, one that has certain genes expressed or unexpressed, is used, certain genes must first be forced to ?turn on? in order for the cell to divide and then its offspring to differentiate again. In both cases, whether using a differentiated or undifferentiated cell as the original, the nucleus must be isolated and extracted from the cell and then placed into an embryonic cell from which the nucleus has been removed. Then, that cell must be forced to begin to divide without fertilization. At this time, there is no better way to accomplish the task than a steady hand, a slew of enzymes, and a imperceptibly tiny pipette, yet what process will be developed in the future is still unknown .

Still, it is not the procedure that causes ethical debate, but instead the uses of this relatively new biotechnology. Some believe these uses outweigh any sort of moral restraints, yet others are shocked and even horrified by them. And such varying types of applications for cloning often cause many varying opinions as well. Cloning can theoretically be used for the mass production of medications, by editing the genes of cloned animals, forcing them to produce these medications in their milk, thereby increasing the availability and decreasing the cost of such drugs . Couples who wish to have children but for some reason have difficulty doing so can make multiple copies of a woman?s egg which can then be fertilized artificially, through in vitro fertilization, increasing the possibility of fertilizing an egg which may come rarely from about 10% to about 50%. In another case, a women who is at a high risk of becoming sterile through chemotherapy or the like may be able to have an embryo cloned for future use. Or, since researches have developed tests for screening for genetic diseases?tests which often kill the embryo, embryos can be cloned to eliminate the risk of damaging such cells in the process .

On another extreme, however, are the ideas of body farming. Cloning could theoretically be used to create a duplicate of a person, removing its higher brain functions early in development, so that the clone can be used to provide vital organs in case the person damages one. In this way, there would be no danger of rejection either, since the body part would be identical in genetic make up to the damaged one. Even more extreme are some other ideas. Entire populations could be created through cloning, isolating specific desirable traits, thereby creating the ultimate in artificial selection. In addition, entire armies, genetically identical, could be created at will, and even clones of long dead personalities of the likes of Hitler and Einstein could be created . Or how about replacing a lost family member with a clone? Or selecting the child you want from a catalog of embryos available to be cloned? While these ideas may seem far fetched, certain events already occurring lead one to believe that such things could actually happen?take for example the father who had a vasectomy reversed to impregnate the mother, a 39 year old woman, in order to produce a child for the sole purpose of creating a donor of bone marrow the ill first child .

While some of these possibilities may seem extreme or entirely plausible, everyone seems to have a different opinion. While increasing the chances of artificial fertilization may seem like a good idea to some, others worry about what will happen to left over embryos, still carrying the possibility of life, when the parents die or when the genetic screening or in vitro fertilization is complete. No one yet knows the answer, for a committee discussing these concerns has yet to be formed. And while the availability of extra organs may be useful in shortening the organ-donor waiting lists, some believe that creating a brain dead class of humans used only to provide body parts is no better than slavery or the suppression of a people. In addition, the production of societies based on clones frightens people afraid of losing their individuality. At the same time, it has also been argued that the best advances come from a variation of people and ideas?the theory that variety causes change. And, the idea of replacing a family member with a clone seems just morally unethical to some .

No matter what a person?s view, anyone can be certain that society, religion, and upbringing play a definite role in the decision. Views on abortion and when life begins, for instance, can have an effect on the importance of an embryo. And, with so many different possibilities for the use of cloning, it is no wonder that a gradient exists between those entirely against cloning and those entirely for it. To illustrate this, a study done of 500 adult Americans, taken by TIME/CNN showed some interesting results (see attached file). It is difficult too to decide on a legal policy governing cloning experiments because of this reason and because of the multiple government agencies that could possible by involved in such a decision. In all, it is a confusing debate which seems to have no answers, for now holding back a ripe area of scientific discovery. It will be interesting to see what finally does develop of this issue.

References

Cimons, Marlene. ?Human Embryo Research Poses Ethics Dilemma.? Los Angeles Times. 25 Sept. 1994: A1+.

?Clone.? Encyclopedia Britannica Microp?dia, 1985 ed.

Elmer-Dewitt, Philip. ?Cloning: Where Do We Draw the Line?? Time 8 Nov. 1993: 64-70.

Lawren, Bill. ?Bionic Body Building.? Longevity Jan. 1991: 22-27.

Weiss, Rick. ?The Ethics of Cloning: Who Decides?? Washington Post. 16 Nov. 1993: 12+.




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