Monday, December 2, 2019
Stem Cell Essay Example
Stem Cell Essay Cells that can differentiate into various cell types are called stem cells and include embryonic stem (ES) cells and adult stem cells. Because ES cells can become a new organism or can differentiate into any tissue type, they are said to be ââ¬Å"totipotent.â⬠Adult stem cells, on the other hand, because they cannot (as far as we know) become any type of tissue, are said to be ââ¬Å"pluripotent.â⬠For example, bone marrow stem cells can become red blood cells, T-lymphocytes, or B-lymphocytes, but not muscle or bone cells. Nerve stem cells can also become different types of nerve tissue. Stem cell research attempts to engineer tissues from the bodys stem cells to replace defective, damaged, or aging tissues. In 1998, scientists were able to grow human ES cells indefinitely. Since then, researchers have conducted stem cell experiments on mammals and have had some success in repairing spinal chord injuries in mice. Because scientists cannot use federal funds to conduct research on embryos, private corporations, most notably the Geron Corporation, have funded ES cell research. Geron, in anticipation of potential ethical concerns, appointed its own ethics advisory board (Lebacqz et al. 1999). The Clinton administration sought to loosen the interpretation of the ban on embryo research to allow the government to sponsor research on the use of ES cells once they were available, but not on the derivation of those cells; it is unclear how the Bush administration will react to this idea. President G. W. Bush had made the decision to allow use only of about 60 existing cell lines, and not the production of embryonic cell lines specifically made for the purpose of use for stem cells. (Kant Patel, Mark Rushefsky, 2005) We will write a custom essay sample on Stem Cell specifically for you for only $16.38 $13.9/page Order now We will write a custom essay sample on Stem Cell specifically for you FOR ONLY $16.38 $13.9/page Hire Writer We will write a custom essay sample on Stem Cell specifically for you FOR ONLY $16.38 $13.9/page Hire Writer Most of the stem cell procedures proposed to date would use the ES cells from embryos created by couples in fertility clinics. In the United States, thousands of embryos are discarded each year because IVF couples cannot use all of their embryos. A couple may create 300 embryos in an attempt give birth to one child. Another approach to stem cell research proposes that researchers create embryos for scientific and medical purposes. This approach, known as therapeutic cloning, or somatic cell nuclear transfer (SCNT), involves transferring the nucleus from a cell in a persons body into an enucleated egg. The ES cells from this new embryo would match the tissue in the persons body, thus avoiding the potential tissue rejection problems that could arise in stem cell therapy. The potential of stem cell research is enormous, because so many diseases result from tissue damage. Stem cell research could lead to advances in treating paralysis, diabetes, heart disease, pancreatitis, Parkinsons di sease, liver disease, arthritis, and many other conditions. The main objection to this promising research has to do with the source of ES cells. ES cells can be obtained from aborted embryos, embryos remaining after infertility treatments (IVF), embryos created solely for research by IVF techniques, and from SCNT techniques (i.e., therapeutic cloning). To obtain ES cells, therefore, one must either create embryos that will be used, manipulated, or destroyed, or one must obtain embryos leftover from infertility treatments. But here is where the abortion debate resurfaces, because these techniques would involve treating embryos as mere things or objects and would not give embryos the respect they deserve, according to some critics. If one views embryos as human beings with dignity and rights, then one should refrain from ES cell research, because this would be equivalent to using human beings in an experiment without their consent, murdering human beings, and so on. Using embryos from abortions is problematic, according to critics, because this practice can encourage abortions. The NBAC (1999) report on this topic recommends that embryos merit respect as a form of life but that they do not merit the same respect as adult human beings. The NBAC made several recommendations, among them, separating the abortion decision from the procedure to use fetal tissues, and that there should be no payment for fetal tissues. Scientific researchers propose to pursue a particular line of research and often have a preferred direction in which they want to go; they (and their lay supporters) hold that the research may be valuable in its results but do not say that it is morally obligatory; if there are objections to the research on ethical or social grounds, the researchers try to modify their work to respond to the criticism; and if the results prove not to be promising, the researchers move in another direction. (David Magnus, 2006) The morally hazardous form of the research imperative responds differently. The proposed research is called morally obligatory, and it is either said or implied that the chosen research direction is the only or the incontestably superior way to go; its proponents dismiss critics of the research as ignorant, fearful, or biased and make only superficial changes to mollify them; and when the research fails to pan out or is slow in coming, they take that fact to show that more research money is needed or that ethical hand-wringing and groundless anxieties have stood in its way. Strikingly, for all the hostility it generated, research on violence in particular and on behavioural genetics more generally has not relied on the moral imperative language even though its supporters believe it can be of great value. At the same time, the researchers have been sensitive to the main line of criticism, that the research results can be misused, and they have been quick to object to media distortions or the excess enthusiasm of some of their colleagues. The flavour changes with fetal cell, embryo, and stem cell research. The scientific claims grow more extravagant, the moral language rises to the highest register, and objections to the research are mainly explained away rather than being taken seriously. ââ¬Å"Therapeutic cloning (or cell replacement by means of nuclear transfer) is a new medical technology that has the potential to transform medicine â⬠¦ this research is not only ethically permissible but imperative.â⬠(Robert P. Lanza et al., 2000) The National Bioethics Advisory Commission held that ââ¬Å"research that involves the destruction of embryosâ⬠¦is necessary to develop cures for life-threatening or severely debilitating diseases and when appropriate protections and oversight are in place to prevent abuseâ⬠.à (National Bioethics Advisory Commission, 52) The implications of that sentence are that no other line of research can be fruitful, and that there is no abuse in destroying embryos. But the former claim is excessive, and the latter at the very least contestable. That same report did say that, in a broad way, the potential benefits of research are not necessarily sufficient to morally justify it, and that limits on science are sometimes necessary. But it did not set many limits to this kind of ââ¬Å"necessaryâ⬠research, at least none that will hold up in a serious way. ââ¬Å"Imperativeâ⬠is inappropriate language to use in seeking public money to carry out embryonic stem cell research; it is even less appropriate to use as a moral trump card to beat down ethical objections. A British physician and medical editor, Richard H. Nicholson, noted how, in Great Britain, the director of the Wellcome Trust claimed that 10 percent of the population would benefit from stem cell research. He added that, ââ¬Å"however outrageous the claims, government ministers and members of Parliament alike believed themâ⬠¦ the wider risks to societal beliefs about the value of human life, if one devalues the embryo, were hardly considered.â⬠(Richard H. Nicholson, 2001) The same has been true in the United States, with excessive hype for the research (few informed scientists and enthusiastic ethicists or legislators urged caution in evaluating the claims), and a campaign to discredit opponentsââ¬âand nothing could do that better than calling them the â⠬Å"religious right.â⬠As the hostilities that developed in response to the XYY controversy and the development of the field of behavioural genetics demonstrated, a fear of the misuse of scientific knowledge has marked many of the debates. An objection to human cloning is not simply that it could deprive a cloned person of his own genetic identity, but also that it will move even further in the direction of ââ¬Å"boutique babiesâ⬠and the dehumanization of procreation. The social implications of research are surely worthy of consideration, and relevant in judging its value, two qualifications are in order. One of them is that it is difficult to know whether imagined social implications will in fact turn out to be true; and the other is that the way we deal with the implicationsââ¬âeven if they come trueââ¬âmay make a great difference in their eventual social impact. The massive use of prenatal diagnosis in India to eliminate unwanted female children could not easily have been foreseen, for ex ample, even if some use for that purpose could be. Looming over these two qualifications is a still more important question: how are we to measure potential risks and benefits of the research, particularly when the benefits are social and not more narrowly medical? Save for historical precedent, if there is any, nothing is more difficult (but not impossible) than trying to predict the social implications of gaining new knowledge or developing new technologies, whether the discovery of electricity, splitting the atom, the invention of the airplane, or the impact of saving lives that once would have ended much earlier. While human reproductive cloning, for instance, does not offers any prospect of benefit to anyone except perhaps under rare circumstances for a tiny minority of infertile couples. But then neither has anyone specified the benefit that cloning will bring to the lives of children. The discussion of alleged benefits is parent-centered, not child-centered. Those critical of behavioural genetics have, by contrast, the historical experience of the ill-fated eugenics movement to cite, and plenty of evidence about the way people can get stigmatized and marginalized by alleged genetic traits or predispositions. Those worries should not be decisive in stifling any and all behavioural research, but they do offer an empirical base for concern about the harmful potential use of the knowledge, and a strong incentive for the researchers to take great care in describing the meaning and value of their research. Of course most researchers try to handle their findings cautiously and articulate them sensitively to guard against their misuse. But there is no way, finally, for them to control what others do with the knowledge or techniques they develop. That is a good reason to be cautious and realisticââ¬âcautious about potential harms yet realistic that not much may be done to avoid some of them even with the best will in the world. But the potent ial for misuse of otherwise valid research, conducted for serious reasons, does not in itself provide adequate grounds to stifle it. The safety of a proposed line of research raises related problems. To this day many recall the worries about safety that marked the early work on in vitro fertilization. The theologian Paul Ramsey was one of the most eloquent writers on the danger that such research posed for any child so procreated. But when baby Louise Brown was born in 1978 and developed in a normal and healthy way, those worries were blown away in an instant, even though the researchers never did reveal how many missteps it took to get to Louise Brown. The failure of recombinant DNA research to produce any flagrant safety problems for the researchers or the general public in the 1970s was, as indicated above, taken as a cautionary tale by many scientists about the damage done by taking private worries to the public. It was hard not to recall those incidents when NBAC called for a five-year moratorium on human cloning research solely on the grounds of a threat to the health of children so cloned. Possible harms are easy to project but their chances of materializing are not. Moreoverââ¬âto recall another feature of the early IVF researchââ¬âin the early 1970s when the researchers clearly realized that there was a great deal of opposition to their work they went underground; or, more precisely, they continued the research but released no preliminary findings or did anything else to call attention to their work. If they were betting that success would silence the critics, it was a bet that paid off handsomely. Will anyone be astounded to hear, a few years from now, that researchers working in the private sector, free of bans, have managed to clone a healthy childââ¬âand that the failures along the way (or likely to occur later) will not be revealed? Since there is no known social benefit in reproductive cloning, even if successful, there is no warrant for running any of those risks. Humanity in the past has produced many evils and still does into the present. The absence of human reproductive cloning does not appear to be the cause of any of them. Hence, the social risk of research that might change basic human institutions for the worse in order to gain small, very small, social benefitsââ¬âin this case procreationââ¬âis worthy of the most careful attention. It is also the most difficult kind of assessment to carry out, if only becauseââ¬âas history has amply shownââ¬ânothing is much harder than judging the long-term consequences of new knowledge. Yet it is important to attempt such assessments, and a fine research project would be to see if some sophisticated methods. (Glenn Mcgee, Arthur L. Caplan, 2001)
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