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Реферат на тему Cloning Essay Research Paper When one thinks

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Cloning Essay, Research Paper

When one thinks of cloning, what comes to mind? Movies such as ?Multiplicity? can give the layperson a much-distorted image of cloning. In this particular movie, actor Michael Keaton plays a father who cannot handle his crazily busy lifestyle. In an effort to be the perfect father, husband and employee, he has himself cloned easily at a nearby medical center. The three clones each have their own personality: one is sarcastic and bitter, one is sweet and sensitive and one is a half-wit but all are identical. This cloning process is false. At this time, scientists have cloned animals including Rhesus monkeys, mice and probably the biggest breakthrough: sheep. Cloning could mean hope for so many different diseases. The advancement of cloning in a medical laboratory should be encouraged. Cloning could save transplant candidates. According to Larry Reibstein and Gregory Beals, companies such as Alexion Pharmaceutical are already beginning to experiment with ways to grow hearts and kidneys in pigs that will not be rejected in transplants (58). Perhaps another reason to encourage cloning is for the treatment of spinal cord injuries. Cloning could give hope to couples unable to have children of their own. By advocating cloning, doctors may find a way to cure or even prevent genetic diseases. Perhaps, though, the most important reason to advance cloning in the laboratory is to treat leukemia?s and cancers. Very possibly, through cloning and genetic engineering, the growth of poorly formed cells could be stopped immediately.

One reason to clone is hope for organ transplants. Currently organ transplantation is considered by some to be a routine process, but the waiting can be tedious, difficult, and nonetheless expensive for the patient while a match is located. The suffering candidate is typically put through a battery of tests and interviews by a physician and a psychiatrist so see if he or she is physically and mentally capable for a transplant. Many factors such as blood type, tissue type, weight and age are all deciding factors for a transplant to avoid rejection of the organ. For instance, a 50-year-old woman who weighs 250 pounds with type O positive blood would probably not take well to heart harvested from a 19 year old with the same blood type who weighs only 100 pounds. The organ should be in correct proportion with the person?s body weight. Many transplant candidates die while waiting for an organ, whether it be a heart, lung, kidney or liver. Yes, it is true that thousands of people are saved each year by organ transplantation, yet even more die each year waiting while their organs shut down. ?In perhaps the most dramatic example, the American Heart Association reports that only 2,300 of 40,000 Americans who needed a new heart in 1997 got one.? (Mikos and Mooney 2). The new strategy that seems promising is the development of what Dr. David J. Mooney of the University of Michigan and Dr. Antonios G. Mikos of the M.D. Anderson Cancer Center in Houston call ?neo-organs.? (3). In one aspiring procedure, the patient receives cells that have been harvested previously and comprised into 3-dimensional molds of biodegradable polymers, such as those used to make dissolvable sutures. The entire structure would be transplanted into the site where cells replicate and form new tissue.

Simultaneously, the artificial polymers dissolve leaving the ?neo-organ?, a natural, formed organ. Applications are already being applied to fabricate skin grafts for wounds, and cartilage, bone and tendons for internal injuries. The possibility of creating complex organs such as kidneys, livers, bladders and breasts is apparent. The proof can be found in the developing embryo where a small group of cells finds the way to form into a complex being with multiple organs capable of a vast number of functions. Theoretically all scientists have to do is discover the details by which a liver becomes a liver, or a lung a lung. In addition, to regenerate other organs, such as a liver, the characteristics of their development must be identified and produced reliably (Mikos and Mooney 5-9).

Presently paralysis has no effective cure. A quite unreliable and still experimental technique that is used hooks the paraplegic victim up to multiple electrodes and shocks the nerves of the lower extremities to stimulate a jerk. The person may be able to walk, but very awkwardly, and requires much assistance. Perhaps, if cells of the spinal cord and commanding neurons could be cloned in a laboratory and implanted in the paralyzed invalid, the use of the patient?s limbs could be regained. It is understandable that anyone might be against this procedure because the nervous system is complex and treatment is rarely successful, but more research on cloning could provide hope to those who are wheelchair bound. Patrons of the Human Cloning Foundation (HCF) firmly believe that by continuing experimentation and research, scientists may learn to grow nerves of the spinal cord back again when they are damaged. Famous quadriplegic, former actor, Christopher Reeves, might be able to rise up from his wheelchair and walk once again (Human Cloning Foundation 3). In research centers around the world, technologists have been perfecting innovative grafting techniques that fill spaces and connect the broken circuits of spinal nerves. Operations in the lab appear hopeful allowing European rats to stand and quadriplegic American cats to walk (Zacks 1).

Cysts and degenerative disorders of the spinal cord can also be treated by this cloning technology. Fetal-cell grafts, using the cells of human embryos can terminate these very damaging cysts and end the danger that they pose on neural function. In Stockholm, Sweden at the Karolinska Institute, three patients have undergone the still experimental procedure and in each case, magnetic resonance imaging (MRI) has shown that the grafted cells grew to fill the gap and live stably within the spinal cord, states neurosurgeon Scott P. Falci (Zacks 3).

Yet, another reason to value cloning technology is to give an infertile man or woman the chance to conceive children of his or her own. With cloning, couples that could not bear children of their own may be able to have children. The current infertility treatments are estimated to be only 10 percent successful. Couples can easily spend thousands of dollars to end up with nothing but pain: physical, emotional and financial. Women who cannot carry children can have a child of their own by implanting a zygote comprised of their egg and their husband?s sperm into a surrogate mother (HCF 2-4). Men who cannot fertilize an egg can obtain a donor sperm and re-synthesize the donor sperm with their own DNA. What is the ending result? In both instances, a healthy child with traits from each parent is the result.

Steen Willadsen and his colleagues: Jacques Cohen and Satiago Munne at St. Barnabas Medical Center in Livingston, New Jersey, in one experiment fuse an eight cell embryo with a very immature cow egg. The chromosomes of the embryonic cell are pushed into metaphase. From metaphase, these cells can be ?karyotyped? (a sorting and examination of chromosomes) rather rapidly. Remarkably, the embryo did not show any signs of any chromosomal defect so; it was implanted in a woman. Approximately nine months afterward a healthy child was delivered. ?It takes very few cells, is very effective and takes very little time.? Says Willadsen (Cohen 3). These reports, so far, give a great deal of promise to couples wanting children.

A fourth reason to consider cloning is the prevention and remedy of genetic diseases. Numerous genetic diseases and conditions that impair and even cause the death of those inflicted could benefit from cloning. Disorders such as Alzheimer?s disease, Parkinson?s disease, diabetes, degenerative joint disease, Tay-Sachs disease and cystic fibrosis are just a few problems that may be curable if cloning and its technology are not banned (HCF 1).

By combining genetic engineering with cloning, the breakthroughs could allow scientist some insight on how to perfect the treatment of fatal diseases. Ailing convalescents will be free of rejection by their own immune systems (HCF 1). In a rare degenerative disorder, syringomyelia, a syrinx, or fluid filled cavity forms a scar near or on the spinal cord. Left untreated, the cavities cause unbearable pain as well as a gradual loss of sensory and motor skills. The traditional remedy involves an operation in which the spinal depressions are drained via an interposed tube. Doctors Richard Fessler, Paul Reier and Douglas Anderson of the University of Florida say that these tubes often become blocked and the patient requires more and more operations. The new techniques offer a far more favorable outcome. ?During the experimental surgery, doctors first drain the syrinx and inject it with spinal cord cells taken from human embryos.? (Zacks 2). The idea is to keep the passageways clear and prohibit them from refilling.

Ian Wilmut, creator of the famous cloned sheep, Dolly, and his colleagues are working on better ways to treat cystic fibrosis, another life-threatening genetic disease (HCF 3). With cystic fibrosis, bodily secretions are unusually thick and gummy and clog the lungs, digestive tract and sweat glands. This causes a horde of problems for the patient. Babies diagnosed with cystic fibrosis are prone to lung infections, have difficulty breathing and eating. Numerous medications merely alleviate some symptoms, but most patients still do not live past the age of 30.

The final and perhaps most important reason to clone is for cancer, which is second to cardiovascular diseases in the leading causes of adult deaths in the United States. When cancer multiplies, it cannot be stopped without the use of strong medications. One of the most popular treatments for cancer is chemotherapy. Chemotherapy works well in killing cancer cells, but it also kills the healthy cells. ?During treatment, I was in and out of the hospital, I reacted so poorly to chemotherapy. Sometimes I could not even keep water down. I lost almost ? of my body weight and had terrible sores on my mouth and skin.? Recalls one cancer patient while on chemotherapy. Some believe it does more harm that good and some patients quit after only one or two chemotherapy sessions because the drugs make them violently ill. Traditional treatments including chemotherapy can guarantee remission rates up to 90 percent, but this newest technology, angiogenesis, an outcome of cloning, can guarantee a remission rate 99 percent for localized (stage 1) cancers (Koczab 2). Even Dr. Folkman himself says, ?I?ve been waiting for results like these my whole life.?

Cancer is the result of disordered and disorganized cell growth and is classified to the cell from which it originated. In the past, cancer was an automatic death sentence because medical professionals did not understand how to kill the cancer without killing the patient. Scientists still do not know exactly how cancer cells are formed and how they lose their differentiation. Cloning may at last be the key to understanding differentiation and cancer (HCF 3).

One of the newest treatments for cancer is called angiogenesis. Dr. Moses Judah Folkman recently discovered Angiogenesis and it seems like a promising cure for localized cancers and tumors. Angiostatin and endostatin are injections that stifle blood vessel growth when injected into human cancers cloned in mice (Begley and Kalb 2). In other words, these injections cause cancers to shrink without harming the cancer-laden person with virtually no side effects. Folkman surmised that to grow, tumors needed blood and send out an unknown substance that coaxes nearby blood vessels into sprouting new capillaries. Angiogenesis prohibits blood vessels from sprouting and the tumor is choked off. This new treatment has proven effective in human cancers grafted and cloned in both mice and rabbits with no apparent side effects. Once bed-ridden cancer patients may be able to relish in a semi-ordinary lifestyle while undergoing angiogenesis injections as treatment.

Another popular treatment for blood-specific cancers such as leukemia?s, myeloma?s and lymphomas is bone marrow or stem cell transplants. Transplanting these fluids from person to person can be just as risky as organ transplantation and the body can reject the solutions. Perchance if some of the healthy bone marrow or stem cells could be withdrawn from the patient himself, cloned in a controlled laboratory and given back to the patient intravenously rejection could be completely avoided. With the mastery of cloning technology, essentially anything is possible.

Scientists at the Fred Hutchinson Cancer Research Center and the University of Washington have mapped the section of a gene identified with the hereditary form of prostate cancer. Locating these genes is one of the most important steps in treating cancers, especially the kinds that run in families, declares Dr. Elaine Ostrander, head of the genetics program at the Hutchinson center (1).

As one can see, cloning could mean hope for measureless amounts of problems and diseases that exist. The fears of rejecting a transplanted organ or substance such as bone marrow and stem cells could be eliminated in the minds of transplant candidates and cancer patients. Paralyzed victims could regain use of their ineffective limbs and gain better motor and sensory skills. Infertile couples could effortlessly have a healthy child of their own. Cataclysmic genetic diseases such as cystic fibrosis, which takes its victims young, could be cured and possibly even prevented. Even cancer could be cured if scientists work at understanding the process by which cancer cells lose their differentiation.

The benefits of cloning outweigh the few religious beliefs that are holding back research that could benefit a large number of people. Some ethicists argue that if the persistence of cloning research continues, soon whole human being clones will all be running around with no sense of identity. This is ridiculous. Of course, laws would be passed against this process and cloning would be strictly limited to treating medical conditions and helping couples have babies. Cloning an identical human being just to harvest their organs or bone marrow is not exactly ethical. Cloning human beings would serve no audible purpose anyhow. In contrast, however, ??if a sterile second-generation Holocaust survivor wanted a male heir to continue an otherwise doomed family line, the rabbi says he might advise the man to clone rather than use donor sperm.? (Woodward 60).

Ethical issues play a role in almost any venture people become associated with. Controversial topics such as gun control, abortion, assisted suicide and cloning all have their advantages and disadvantages. ?Humans have devoted much thought to the idea of ?playing God.?? (Masci 418). The real crux here is how far do scientists go.

Works Cited List

Beals, G., Reibstein, L. Newsweek (cover story) 10 Mar 1997: 58.

Begley, S & Kalb, C. ?One Man?s Quest to Cure Cancer.? Newsweek. 18 May 1998.

Cohen, P. ?Dolly Helps the Infertile. World Wide Web. AOL 19 May 1999 [www.newscientist.com]

?Human Cloning.? World Wide Web. AOL. 24 Apr 1999. [www.humancloning.org/]

Masci, David. ?The Cloning Controversy.? The CQ Researcher. 9 May 1997: 409-431.

Mikos, Antonios G. & Mooney, David J. ?Growing New Organs.? World Wide Web. AOL. 17 May 1999. [www.sciam.com/1999/0499issue/0499mooney.html]

?New scientist.? World Wide Web. AOL 25 Apr 1999. [www.newscientist.com/nsplus/insight/clone.html]

Ostrander, E. ?Seattle Researchers Zero In On Location of Gene for Inherited Prostate Cancer?? World Wide Web. AOL. 23 May 1999.

?Spinal Cord Repair.? World Wide Web. AOL. 19 May 1999. [www.sciam.com/explorations/081897spinal/zacks.html]

Woodward, Kenneth L. ?Today the Sheep?? Newsweek 10 Mar 1997: 60.


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