РефератыИностранный языкClCloning Essay Research Paper The idea that

Cloning Essay Research Paper The idea that

Cloning Essay, Research Paper


The idea that humans might someday be cloned has started sounding less like a science fiction


novel and more like a genuine scientific possibility. On February 23, 1997, The Observer broke the news


that Ian Wilmut, a Scottish scientist, and his colleages at the Roslin Institute were about to anounce the


successful cloning of a sheep by a new technique which had never been successfully used before in


mammals. This technique involved transplanting the genetic material of an adult sheep, obtained froma


differentiated somatic cell, into an egg from which the nucleus had been removed. The resulting birth of a


sheep named Dolly on July 5, 1997, was different from prior attempts to create identical offspring since Dolly


contained the genetic material of only one parent, which therefor emade her a “delayed” carbon copy of a


parent which had contributed her genetic makeup, with a member of the opposite sex only filling in her


genetic makeup wherever it was absolutely necessary in the creation process.


Since the birth of Dolly public debates have sprung up all over the world. Although cloning of


humans may be clinically feasible, discussion of the ethical, legal, and social issues raised are important.


Cloning is just one of the several techniques potentially available to select, control, or alter the genome of


an offspring. The developement of such technology poses an important challenge: how to ensure that the


technology is used to enhance, rather than limit, individual freedom and welfare. A key ethical question is


whether a responsible couple, interested in rearing healthy offspring biologically related to them, migt


ethically choose to use cloning, or other genetic selection technique for that purpose. The answer should


take into account the benefits sought through the use of the techniques and any potential harm to offspring


or to other interests. The most likely uses of cloning would be far removed from the bizarre or horrific


scenarios that initially dominated media coverage.


Clonging humans is actually quite simple, when thought of relevently. The procedures used in


cloning human embryos are very similar to that of cloning animal embryos. To clone a human embryo, one


must first acquire a sperm cell and a mature egg cell and combine them. The “home made” embryo is placed


in a petri dish and allowed to develop into a mass of two to eight cells. Next a chemical solution is added


that dissolves the zona pellucida that covers the embryo. The zona pellucida is a protective preotein and


polysaccharide membrane that covers the internal contents of the embry, and provides the necessary


nutrients for the first several cell divisions taht occur within the embryo. After the zona pellucida is


dissolved the cells within the embryo are freed. These two to eight cells are then collected by the


researchers and placed in seperate petri dishes. These embryonic cells are called blastomers, or cells that


are part of a hollow ball of cells known as the blastula. The embryonic cells are then coated with an


artificially produced zona pellicuda. The individual cells then are considered new embryos, all of which


share the exact genetic information and composition. These cells will continue to divide and eventually will


form a human being if allowed to develop.


The main issue as to whether or not human cloning is possible throught the splitting of embryos


began in 1993 when experimentaion was done at George Washington University Medical Center in


Washington, D.C. There Dr. Jerry Hall experimented with the possibility of human cloning and began this


moral and ethical debate. There it was conducted that cloning is not something that can be done as of now,


but it is quite a possibility for the future. These scientists experimented eagerly in aims of learning how to


clone a human. Shannon Brownlee of U.S. New and World Report writes, “Hall and other scientists split


single human embryos into identical copies, a technology that opens a Pandora’a box of ethical questions


and has sparked a storm of controversary around the world.” They attempted to creat seventeen human


embryos in a laboratory dish and when it had grown enough, seperatedthem into forty-eight individual cells.


Two of the seperate cells that survived for a few days in the lab developed into new human embryos smaller


than the head of a pin and consisted of thirty-two cells each.


Although we have yet to truly clone an actual human being , when this experiment occured, it


caused almost an ethical emergency. Many questions were asked, but they were all related to one thing.


The question is, can we and should we use the biotechnologies of genetic manipulation and cloning to


improve the human condition? What are exactly the percieved risks and benefits of eugenics? Some people


may think that biologist are cloning human embryos only to see how far they can push the scientifica


envelope, but there are many legitimate reasons for investigating cloning. Embryologists believe that


research into cloning could help improve the life of future generations. Many biologists believe that they


have a personal duty to the improvement of society, perhaps even a moral obligation. To this end the


techniques of embryonic cloning and alteration have been offered to society as an option for the


improvement of humanity. Doctors hope that by being able to study the multiple embryos developed


through cloning, they can determine the causes of spontaneous miscarriages. Contraceptive specialists


believe that they can determine how an embryo knows where to implant itself, they can develop a


contraceptive that would prevent embryos for implanting themselves in the uterus.


There are many excited parents looking forward to this breakthrough in technology. By looking at


the many different reasons for cloning a child, one can better understand why it may seem appealing to


parents. Cloning form an already existing human will provide the opportunity for parents to pick their


“ideal” child. They will be able to pick out every aspect of their child and make sure that it is perfect even


before they decide to have it. For example, they can choose their hair and eye color, and build almost


ex

actly by looking at the individual they were cloned from.


If the husband were the source od DNA and the wife provided the egg that recieved the nuclear


transfusion and then gestated the fetus, they would have a child biologically related to them and would not


need to rely on an anonymous gamete or embryo donation. Of course, many infertile couples might still


prefer gamete or embryo donation, or maybe even adoption. But is there really something inherently wrong


with wishing to biologically related to one’s child, even when this goal cannot be reached through sexual


reproduction? A second plausible application would be for a couple at high risk of having offspring with a


genetic disease. Couples in this situation must now choose whether to risk the birth of an affected child, to


undergo prenatal and preinplantation diagnosis and abortion or the discarding of embryos, to accept


gamete donation, to seek adoption, or to remain childless. If cloning were available, however, some couples


, in line with prevailing concepts of kinship, family, and parenting might strongly prefer to clone one of


themselves or another family member. Alternatively, if they already had a healthy child, they might to use


cloning to create a later born twin of that child. In the more distant future, it is even possible that that the


child whose DNA was replicated would not have been born healthy, but would have been made healthy by


gene therapy after birth. A third application relates to obtaining tissue or oragns for transplantation. A


child who need an organ or tissue transplant might lack a medically suitable donor. Couples in this situation


have sometimes concieved a child in hope that he or she would have the correct tissue to serve, for example,


as a bone marrow donor for an older sibling. If the child’s disease was not genetic, a couple might prefer to


clone the affected child to be sure that the tissue would match. It might eventually be possible to procure


suitable tissues or organs by cloning the source DNA only to the point in which stem cells or other material


might be obtained for transplanation, thus avoiding the need to bring a child into the world for the sake of


obtaining tissue. Cloning a person’s cells up to the embryo stage might provide a source of stem cells or


tissue for the person cloned. Clonign might also be able to enable a couple to clone a dead or dying child


so as to have that child live on in some closely related form, to obtain sufficient numbers of embryos for


transfer and pregnancy, or to eliminate mitochondrial disease.


cer research is possibly the most important reason for embryo cloning. Oncologists believe that embryonic


study will advance understanding of the rapid cell growth of cancer. Cancer cells develop at approximately


the same phenomenal speed as embryonic cells do. By studying the embryonic cell growth, scientists may


be able to determine how to stop it and also stop cancer growth in turn. Another important area of embryo


cloning research is embryonic stem cell developement. Stem cells are undifferentiated cells that can develop


into almost any type of cell in the body. These cells are not attacked by a person’s immune system, because


of their fast developement and undifferentiated status. Many doctors believe that these stem cells could be


used in treatments for brain and nerve system damage. In adult humans, when damage to nerve tissue takes


place, the nerve tissue does not regenerate and replace the lost tissue. However, since the stem cells are


undifferentiated they could theoretically be used to replace the damaged cells. Human embryo cloning is


needed for the implantation of stem cells, because of the large amount of cells that would be needed.


Genetic screening is a branch of cloning that is already being used in hospitals in England. Parents


who have histories of genetically inhereited diseases, such as cystic fibrosis, can use embryo screeninhg to


deteremine if their child has recvieved the defective gene. Several embryos can be developed via invetro


fertilization procedures, and then be cloned. The DNA from one of the cloned embryos would then be


removed and standard genetic testing, using riflips, would be used to detect whether or not that embryo


contains the genetic disease. If the cloned embryo does not contain the defective gene, then one of the


other identical embryos can be used for implantation in the parent. This would almost guarantee that the


child would be free of genetic disease.


Perhaps a more questionable use of cloned embryos is for spare parts. It is possible that parents


could decide to use one cloned embryo for implantation and eventual birth of a child, and save any spares


by freezing them. If the child were to become critically sick, and need a bone marrow transplant, one of the


frozen embryos could be thawed and implanted into the uterine wall for developement of another identical


child. The bone marrow form this child could then be used to help save the life of this child, perhaps even


without the necessity of carrying the child to full term. This again raises the question of what moral status a


fetus should have, if any at all?


Using cloning to produce offspring for the sake of their organs is an issue that must be faced and


question whether or not it is morally right. No one will say that it is okay to kill a human being for the sake


of their organs, but many have no objection to cloning thousands of individuals that look alike.


Technology seems to take away many of the moral that we have worked so hard to install in society. Most


people seem to only want to cater to their own needs and do not bother to consider the consequences that


society and the clone may have to face. The issue of invetro fertilization among embryos only leads the


public to fear what may happen once cloning takes over, if it does.


Probably one of the most asked questions about the possibility of a world of clones is how will it


feel to be one clone among that of hundreds? Imagine walking down the street and seeing hundreds of


people that are identical to you, but just go by different names and dress differently. Cloning can be used


to help an individual live, but what will be the cloned individuals view on life?

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