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There exists a widespread '''controversy over stem cell research''', which arises from the techniques used in the creation and usage of [[stem cells]]. In particular, the status of the [[embryo|human embryo]] and [[embryonic stem cell]]s are predictably sensitive topics. This is because, with the present state of technology, creating a [[stem cell line|stem cell 'line']] requires either the destruction of a human embryo, removal of some embryonal cells, and/or [[somatic cell nuclear transfer]], also known as research cloning or therapeutic cloning. The ensuing debate has prompted national and international authorities to seek suitable [[regulation|regulatory frameworks]] and highlighted the fact that stem cell research represents a [[political]], [[social]] and [[ethical]] minefield. However, some believe that the death of a [[zygote]] embryo is outweighed by the milions of patients that, in theory, could be saved once [[stem cell treatments]] have been fully developed.
There exists a widespread '''controversy over stem cell research''', which arises from the techniques used in the creation and usage of [[stem cells]]. In particular, the status of the [[embryo|human embryo]] and [[embryonic stem cell]]s are predictably sensitive topics. This is because, with the present state of technology, creating a [[stem cell line|stem cell 'line']] requires either the destruction of a human embryo, removal of some embryonal cells, and/or [[somatic cell nuclear transfer]], also known as research cloning or therapeutic cloning. The ensuing debate has prompted national and international authorities to seek suitable [[regulation|regulatory frameworks]] and highlighted the fact that stem cell research represents a [[political]], [[social]] and [[ethical]] minefield. However, some believe that the death of a [[zygote]] embryo is outweighed by the millions of patients that, in theory, could be saved once [[stem cell treatments]] have been fully developed.


==Controversy over human embryonic stem cell research==
==Controversy over human embryonic stem cell research==

Revision as of 01:18, 16 October 2006

There exists a widespread controversy over stem cell research, which arises from the techniques used in the creation and usage of stem cells. In particular, the status of the human embryo and embryonic stem cells are predictably sensitive topics. This is because, with the present state of technology, creating a stem cell 'line' requires either the destruction of a human embryo, removal of some embryonal cells, and/or somatic cell nuclear transfer, also known as research cloning or therapeutic cloning. The ensuing debate has prompted national and international authorities to seek suitable regulatory frameworks and highlighted the fact that stem cell research represents a political, social and ethical minefield. However, some believe that the death of a zygote embryo is outweighed by the millions of patients that, in theory, could be saved once stem cell treatments have been fully developed.

Controversy over human embryonic stem cell research

The scientific and medical interest in embryonic stem cells is due to the uniquely undisturbed state of blastomere cells. Once a human egg cell is fertilized with a sperm cell, within thirty hours the two cells merge to form a single blastomere cell. This is the first embryonic stem cell in the development of a human (it is the first cell of the embryo). This single cell divides into 2 blastomere cells. At this point the embryo is called a zygote. The 2 blastomere cells each divide into a total of 4 blastomere cells which, in turn, each divide into a total of 8 blastomere cells. The 3 initial iterations of cell division do not cause the zygote to increase in size, instead the cells become smaller as they increase in number. It is these 8 cells that are used for in vitro fertilization and are the current subject of the debate over human embryonic stem cell research. In embryonic development, the zygote, composed of the 8 blastomere cells, descends down the fallopian tube and attaches itself to the uterus. Then the zygote develops into a morula (32 blastomere cells), a blastula (128 blastomere cells), a gastrula (three different germ layers), and then a blastocyst (thousands of cells). At this point the embryo develops into a fetus, which develops into a new born human (trillions of cells). The 8 blastomere cells of the zygote, prior to descending down the fallopian tube, are undifferentiated cells that eventually divide and differentiate into the vastly different types cells of which a human adult is composed. Exogenous interactions cause a stem cell to differentiate into different types of cells (such as blood cells and neurons). Adult stem cells (such as blood stem cells), in contrast to embryonic cells, have undergone a great deal of exogenous interaction with other cells. This makes adult stem cells very different from the zygote blastomere cells, which are human stem cells in the most undifferentiated and most isolated form. Rigorous scientific and medical research depends on the study of these isolated and totally undifferentiated stem cells.

The status of the human embryo and human embryonic stem cell research is a controversial issue as, with the present state of technology, the creation of a human embryonic stem cell line requires the destruction of a human embryo. Stem cell debates have motivated and reinvigorated the ‘pro-life’ movement whose members have concerned themselves with the rights and status of the embryo as an early-aged human life. They believe that embryonic stem cell research instrumentalizes and violates the sanctity of life and constitutes murder [1]. The fundamental assertion of those who oppose embryonic stem cell research is the religiously motivated belief that human life is inviolable, combined with the opinion that human life begins when a sperm cell fertilizes an egg cell to form a single cell.

Most stem cell researchers use embryos that were created but not used in in vitro fertility treatments to derive new stem cell lines. Most of these embryos are slated to be destroyed, or stored indefinitely. In the United States alone, there are at least 400,000 such embryos.[2] This has lead some opponents of abortion rights, such as Senator Orrin Hatch, to support human embryonic stem cell research.[3]

While the opposition argues that "the line at which an embryo becomes a human life remains as arbitrary as ever" [4], those in favor of embryonic stem cell research assert that the zygote is a collection of eight undifferentiated cells. The medical community additionally counters the moral and ethical concerns by highlighting the promise of stem cell treatments for debilitating diseases that currently have no known cure.

In addition, opponents of human embryonic stem cell research and some scientists argue that embryonic stem cell research is drawing money and resources away from adult stem cell research and cord blood stem cell research.[5] For example, David Prentice, of the pro-life Family Research Council, has stated that the use of adult stem cells from sources such as umbilical cord blood had consistently produced more promising results than the use of embryonic stem cells. Such claims are disputed by supporters of embryonic stem cell research.[6]

Another concern with embryonic stem cell research is the tendency of stem cells from embryos to create tumors.[7][8] They note that adult stem cells have already produced therapies, while embryonic stem cells have not. However, scientists have studied adult stem cells for decades, but first isolated human embryonic stem cells only in 1998.[9]

Some stem cell researchers are working to develop techniques of isolating stem cells that are as potent as embryonic stem cells, but do not require the destruction of a human embryo. Some believe that an adult stem cell can be coaxed to "dedifferentiate" and revert to an embryonic state. Kevin Eggan of Harvard University has attempted to transfer the nucleus of a body cell into an existing embryonic stem cell, thus creating a new stem cell line.[10] Researchers at Advanced Cell Technology, led by Robert Lanza, reported the successful derivation of a stem cell line using a process similar to Preimplantation genetic diagnosis, in which a single blastomere is extracted from a blastocyst.[11] Findings published in August 2006 indicate that differentiated cells can be reprogrammed to an embryonic-like state by introducing four specific factors[12]. This finding, if verified, may allow for the creation of stem cells from adult cells without the reliance on embryonic cells.



Controversy over stem cell treatments

Main article: Stem Cell Treatments

Medical researchers believe that stem cell research has the potential to dramatically alter approaches to understanding and treating diseases, and to alleviate suffering. In the future, most medical researchers anticipate being able to use technologies derived from stem cell research to treat spinal cord injuries, diabetes, Parkinson's disease, and muscle damage, amongst a number of other diseases and impairments.

The anticipated medical benefits of stem cell research have added a certain amount of emotion and urgency to the debates, which has been exploited by medical researchers, seeking to secure funding and legitimacy for their practice. In other words, the medical community has had a tendency to predict the future benefits of stem cell research without giving sufficient recourse to the inherent complexity that comes with such predictions. This has resulted in stem cell researchers being criticised for falsely raising people's expectations, and for portraying the trajectory of innovation in a very linear fashion.[13][14][4]

Such criticism has even come from researchers themselves. For example, in November 2004, Princeton University president and geneticist Shirley Tilghman said, "Some of the public pronouncements in the field of stem-cell research come close to overpromising at best and delusional fantasizing at worst."[15] Similarly, fertility expert and current president of the British Association for the Advancement of Science, Lord Winston has warned of a public backlash against stem cell research if it fails to deliver on some of the "hype" surrounding potential treatments.[16]

These raised expectations may contribute to a lack of oversight of human embryonic stem cell research, and likely contributed to the deceptions and fraud of the scientist Hwang Woo-Suk.

Historians of science have illustrated how difficult it can be to predict the eventual outcomes of innovation. Stem cell research itself is very expensive to conduct and the expected therapeutic technologies may only be made available to those who can afford them. In addition, a public backlash against embryonic stem cell research could stifle innovation. In this context of social and scientific uncertainty, opponents of the research are quick to point out that stem cell technologies are still at a developmental stage and it is virtually impossible to predict the eventual outcomes of innovation in the field.

In fact, some scientists are altering their language, seeing a shift in likely stem cell hopes and perhaps working to lower expectations. Many see stem cell research first as a tool to better understand the biology of diseases, and decreasing imagine cell therapy as the first goal. Others still have high expectations for cell therapy. Thomas M. Jessell, a neurobiologist at Columbia University said, "Many of us feel that for the next few years the most rational way forward is not to push stem cell therapies". Similarly, John Gearhart, of Johns Hopkins University said, "I personally feel that the beauty of these cells is that we'll learn a lot about human biology and disease processes, and that that information will be more important than the cells themselves." [17]

On the other hand, stem cell transplants are an emerging medical practice, with the stem cells often coming from organ donors in the case of eye surgery to cure or prevent blindness. However, successes rates are not as high as patients would hope[citation needed]. Stem cell transplants also play a role in therapy for cancer in cases such as leukemia. It is logical that if stem cells from donated organs provide some degree of successes then a complete understanding of stem cells, which is only possible by studying embryonic stem cells, is very likely to lead to far better treatments.

Controversy over cloning in stem cell research

Proposals to use cloning techniques in human stem cell research, a process called somatic cell nuclear transfer, research cloning, or therapeutic cloning, raise a set of concerns beyond the moral status of the embryo. These have led a number of individuals and organizations who are not opposed to human embryonic stem cell research to be concerned about, or opposed to, human research cloning.

The aim of carrying out this procedure is to obtain stem cell lines that are genetically identical to the donor organism. One possible use would be study the cellular biology of diseases. Another would be to develop patient-specific stem cell lines that would not be rejected by the patient's immune system. However, no stem cell lines have been derived from clonal embryos.

One concern is that cloning in human stem cell research will lead to the reproductive cloning of humans. Both processes use the same first step: the creation of a clonal embryo, most likely via somatic cell nuclear transfer. In research cloning, this clonal embryo will be destroyed in order to attempt to derive a stem cell line. In attempted reproductive cloning, the embryo would be implanted in a woman’s uterus to create a cloned child. Those who hold this concern often advocate for strong regulation of research cloning[18], or its prohibition.[19]

A second concern is the appropriate sourcing of the eggs that are needed. research cloning requires a large number of human eggs, which can only be obtained from women. This is an invasive procedure that carries health risks, such as ovarian hyperstimulation syndrome, and even death.[20] Those who hold this concern call for measures to protect the women who provide eggs, such as requiring a "firewall" between clinicians carrying out the egg retrievals and researchers using the eggs in their work. There are also concerns about the emergence of a market for eggs that would disproportionately lead economically vulnerable women to put themselves at risk. This concern has led to a sentiment that prohibitions on financial compensation to women who provide eggs for research should not be compensated beyond reimbursement of direct expenses. This position has been adopted by the United States National Academies[21] and the California Institute for Regenerative Medicine.[22]

A third concern is the feasibility of developing stem cell therapies from cloning. Some consider that the large number of eggs and the skilled labor required may mean that any such therapies are likely to be impractical or extremely expensive. Prominent researcher advocates such as Alan Trounson ("[T]he so-called therapeutic cloning to my mind is a non-event... it’s just not realistic [as a source of cures].")[23] and Thomas Okarma ("[T]he process is a nonstarter, commercially.") [24] have asserted that such therapies are not practical.

Controversy over patents covering human stem cell research

The patents covering much work on human embryonic stem cells are owned by the Wisconsin Alumni Research Foundation (WARF). WARF does not charge academics to study human stem cells but does charge commercial users. WARF sold Geron Corp. exclusive rights to work on human stem cells but later sued Geron Corp. to recover some of the previously sold rights. The two sides agreed that Geron Corp. would keep the rights to only three cell types. In 2001 WARF came under public pressure to widen access to human stem-cell technology.[25]

These patents are now in doubt as a request for their review by the US Patent and Trademark Office has been filed by non-profit patent-watchdogs The Foundation for Taxpayer & Consumer Rights and the Public Patent Foundation as well as molecular biologist Jeanne Loring of the Burnham Institute. They contend that two of the patents granted to WARF are invalid because they cover a technique published in 1992 for which a patent had already been granted to an Australian researcher. Another part of the challenge states that these techniques, developed by James A. Thomson, are rendered obvious by a 1990 paper and two textbooks.

The outcome of this legal challenge is particularly relevant to the Geron Corp. as it can only license patents that are upheld.[26][27]

International policy context

Embryonic stem cell research has divided the international community. In the European Union, stem cell research using the human embryo is permitted in Sweden, Finland, Belgium, Greece, Britain, Denmark and the Netherlands; however it is illegal in Germany, Austria, Ireland, Italy, and Portugal. The issue has similarly divided the United States, with several states enforcing a complete ban and others giving financial support - see below. Elsewhere, Japan, India, Iran, Israel, South Korea, and China are supportive, Australia is partially supportive (exempting reproductive cloning yet allowing research on embryonic stem cells that are derived from the process of IVF); however New Zealand, most of Africa (excepting South Africa) and most of South America (excepting Brazil) are restrictive.

The Hinxton Group

Medical researchers, ethicists and assorted spokespersons from 14 different countries have published a set of legal and ethical guidelines relating to stem cell research, in an effort to address conflicting international laws in this area [1] [2]. The ‘Hinxton Group’ met recently for the first time, in Cambridge, and published a consensus statement calling for a ‘flexible’ regulatory framework, which can simultaneously accommodate rapid scientific advance and at the same time accommodate the diversity of international approaches towards stem cell science (ibid.). It also recommends that, in countries which oppose embryonic stem cell research, scientists should be free to pursue their research elsewhere (ibid.).

In light of the controversy surrounding Hwang Woo-Suk, the Hinxton Group has additionally recommended a number of measures intended to prevent fraud in stem cell research. The group has requested that all authors of embryonic stem cell papers submit a statement of authenticity of any new cell-lines and that the source of stem cells be clearly specified (ibid.).

On the ethical issues surrounding embryonic stem cell research, the group has additionally recommended that an international database be created, containing guidelines for ethical practice, research protocols, consent forms, and the information provided to donors (ibid.).

However, the potential for an international consensus on these matters seems remote given the complexity and diversity of regulatory frameworks in this controversial area of science, both within nations and between nations.

US policy debate

Origins of policy debate in the U.S.

In 1969, the first human in vitro fertilization was accomplished and in 1973, Roe v Wade legalized abortion nationwide. These developments prompted the federal government to create regulations barring the use of federal funds for research that experimented on human embryos. In 1995, the NIH Human Embryo Research Panel advised the Clinton administration to permit federal funding for research on embryos left over from in vitro fertility treatments and also recommended federal funding of research on embryos specifically created for experimentation. In response to the panel's recommendations, the Clinton administration, citing moral and ethical concerns, declined to fund research on embryos created solely for research purposes,[28] but did agree to fund research on left-over embryos created by in vitro fertility treatments. At this point, the Congress intervened and passed the Dickey Amendment in 1995 (the final bill, which included the Dickey Amendment, was signed into law by Clinton) which prohibited all federal funding for research that resulted in the destruction of an embryo regardless of the source of that embryo. The Dickey Amendment remains the law to this day.

In 1998, privately funded research led to the breakthrough discovery of hESC (Human Embryonic Stem Cells). This prompted the Clinton Administration to re-examine guidelines for federal funding of embryonic research. In 1999, the president's National Bioethics Advisory Commission recommended that hESC harvested from embryos discarded after in vitro fertility treatments, but not from embryos created expressly for experimentation be eligible for federal funding[3]. Even though embryos are always destroyed in the process of harvesting hESC, the Clinton Administration decided that it would be permissible under the Dickey Amendment to fund hESC research as long as such research did not itself directly cause the destruction of an embryo. Therefore, HHS issued its proposed regulation concerning hESC funding in 2001. Enactment of the new guidelines was delayed by the incoming Bush administration which decided to reconsider the issue.

President George W. Bush announced, on August 9, 2001 that federal funds, for the first time, would be made available for hESC research on currently existing stem cell lines; however, the Bush administration chose not to permit funding for research on hESC cell lines not currently in existence, thus limiting federal funding to research in which "the life-and-death decision has already been made" [4]. The Bush Administration's guidelines differ from the Clinton Administration guidelines which did not distinguish between currently existing and not-yet-existing hESC. Both the Bush and Clinton guidelines agree that the federal government should not fund hESC research that directly destroys embryos.

Neither Congress nor any administration has ever prohibited private funding of embryonic research. Also, public and private funding of adult stem cell research has no restriction whatsoever.

Congressional response

In April 2004, 206 members of Congress, including many moderate Republicans, signed a letter urging President Bush to expand federal funding of embryonic stem cell research beyond what Bush had already supported.

In May 2005, the House of Representatives voted 238-194 to loosen the limitations on federally funded embryonic stem-cell research — by allowing government-funded research on surplus frozen embryos from in vitro fertilization clinics to be used for stem cell research with the permission of donors — despite Bush's promise to veto the bill if passed. [5] On July 29, 2005, Senate Majority Leader William H. Frist (R-TN), announced that he too favored loosening restrictions on federal funding of embryonic stem cell research.[29] On July 18, 2006, the Senate passed three different bills concerning stem cell research. The Senate passed the first bill, 63-37, which would have made it legal for the Federal government to spend Federal money on embryonic stem cell research that uses embryos left over from in vitro fertilization procedures. [30] On July 19, 2006 President Bush vetoed this bill. The second bill makes it illegal to create, grow, and abort fetuses for research purposes. The third bill would encourage research that would isolate pluripotent, i.e., embryonic-like, stem cells without the destruction of human embryos.

Current State of Federal Funding for hESC Research in the USA

Currently, the National Institutes of Health has 399 funding opportunities for researchers interested in hESC [6]. In 2005 the NIH funded $607 million worth of stem cell research, of which $39 million was specifically used for hESC [7]. Of the 514 currently recruiting clinical trials that are using stem cells as treatment, the federal government is supporting 206 of them; however, none of these trials are using hESC [8].

Polls regarding embryonic stem cell research

Surveys show majorities of the American public supports stem cell research and would back federal funding for it. For example, somewhat more than half (56%) favored federal funding in a CNN/USA Today/Gallup poll conducted in August 2005.[9] Many people, however, admit to pollsters that they don’t follow the issue closely. Surveys on stem cell research often have “don’t know” responses in the double digits, which often indicate that public attitudes are unsettled and open to change, according to the research group Public Agenda.[10] This is particularly important in surveys on stem cells, where those who are most attentive also tend to be the most supportive.[11]

A systematic review [12] of available polling data by American University Professor Matthew Nisbet [13]finds that in the neutrally worded survey questions sponsored by news organizations and non-partisan survey firms, public support for embryonic stem cell research rests at slight majority levels, ranging between 50% and 60% support. However, support drops when asking about sources of stem cells that do not involve so-called leftover embryos, including embryos created for research purposes or cloned embryos. Public opinion is also strongly susceptible to question wording effects, with many polls showing the greatest support for stem cell research including language that references the possibility of cures for a range of diseases. Since 2001, support for embryonic stem cell research has increased at the national level, but polls show that most of this increase in support has come from Democrats and independents. Following the 2004 Presidential election, polls in late 2004 and 2005 showed for the first time a significant gap between Democrats and Republicans in how they viewed embryonic stem cell research. [14] Other studies find that ideology and religious identity serve as powerful perceptual screens on how Americans make sense of the competing messages about stem cell research. [15]

Republican voters are divided on embryonic stem cell research, according to a survey of 800 conducted by pollster David Winston, who also conducts surveys for the Republican leadership in the House and Senate. 25% of Republicans said they wanted no government funding of the research, 33% favored the limited funding Bush offers, and 36% wanted expanded funding to cover research on leftover embryos at fertility clinics. The Winston poll was sponsored by a group of centrist Republicans, The Republican Main Street Partnership.[16][17][18]

A June 2004 poll conducted by Opinion Research Corp. on behalf of the Civil Society Institute found that three-quarters of 1,017 adults respondents--including 6 in 10 conservatives--supported former First Lady Nancy Reagan's call for fewer restrictions on the research.^ [19]Overall support of embryonic stem cell research by Christians was found to be 73% in a 2004 Harris Interactive poll. Even a majority of people describing themselves as "very religious" were found to support it. [20]

The stem cell debate often draws upon public attitudes about abortion and cloning. Surveys show the public strongly rejects reproductive cloning to create children but is skeptical towards cloning for research.[21] The results of cloning surveys are very dependent on question wording. A 2005 poll by the Genetics and Public Policy Center at Johns Hopkins University found that 76 percent of Americans surveyed did not approve of "scientists working on ways to create a cloned human embryo for research." [31] Cloning was supported by 59% of respondents in a July 2005 poll conducted by Research America, a non-profit organization composed of universities, patient groups and biotech and pharmaceutical companies.[22]

Emerging U.S. state-by-state approach

California voters in November 2004 approved Proposition 71, creating a US$3 billion state taxpayer-funded institute for stem cell research, the California Institute for Regenerative Medicine. It hopes to provide $300 million a year. However, as of June 6, 2006, there were delays in the implementation of the California program and it is believed that the delays will continue for the significant future. [23] On July 21, 2006, Governor Arnold Schwarzenegger (R-Calif.) authorized $150 million in loans to the Institute in an attempt to jump start the process of funding research.[32]

Several states, in what was initially believed to be a national migration of biotech researchers to California [24], have shown interest in providing their own funding support of embryonic and adult stem cell research. These states include Connecticut [25], Florida, Illinois, Massachusetts [26], Missouri, New Hampshire, New York, Pennsylvania, Texas [27][28], Washington, and Wisconsin. New Jersey has since become the second state in the nation to create a state-supported stem cell research institute. [29] Other states have, or have shown interest in, additional restrictions or even complete bans on embryonic stem cell research. These states include Arkansas, Iowa, Kansas, Louisiana, Michigan, Nebraska, North Dakota, South Dakota, and Virginia. (States play catch-up on stem cells, USA Today, December 2004)

UK policy

Since the discovery of hESC in 1998, many nations have revisited their legislation regarding the permissible use of embryos in biomedical research. In 2001, the United Kingdom amended the Human Fertilization and Embryology Act to permit the destruction of embryos for hESC harvests but only if the research satisfies one of the following requirements:

  1. Increases knowledge about the development of embryos,
  2. Increases knowledge about serious disease, or
  3. Enables any such knowledge to be applied in developing treatments for serious disease [30].

The United Kingdom is one of the leaders in stem cell research--in the opinion of Lord Sainsbury, Science and Innovation Minister for the UK. [31]. A new £10 million stem cell research centre has been announced at the University of Cambridge [32]

See also

General

Ethics

World policy

News

References

  1. ^ "The stated reason for President Bush's objection to embryonic stem cell research is that 'murder is wrong'" (BBC)
  2. ^ Weiss, Rick. (May 8, 2003) "400,000 Human Embryos Frozen in U.S.," Washington Post. Retrieved August 24, 2006.
  3. ^ Connolly, Ceci. (July 30, 2005) "Frist Breaks With Bush On Stem Cell Research." Washington Post. Retrieved August 24, 2006.
  4. ^ a b Cite error: The named reference Parry was invoked but never defined (see the help page).
  5. ^ The Coalition of Americans for Research Ethics. "The "Political Science" of Stem Cells". Retrieved on July 16, 2006.
  6. ^ Prentice, David. (October 17, 2005) "Live Patients & Dead Mice". Christiantiy Today. Retrieved on August 24, 2006.
  7. ^ Dolan, Kerry. (July 21, 2006) "Despite Bush Veto, Stem Cell Research Abounds." Forbes. retrieved July 21, 2006.
  8. ^ Clarke, Michael F. amd Michael W. Becker. (July 2006). "Stem Cells: The Real Culprits in Cancer?" Scientific American. Retrieved on August 8, 2006.
  9. ^ Anonymous (September 24, 2006) "Cloning/Embryonic Stem Cells." National Human Genome Research Institute. Retrieved September 24, 2006.
  10. ^ C.Cowan, J. Atienza, D. Melton and K. Eggan. (August 26, 2005) "Nuclear reprogramming of somatic cells after fusion with human embryonic stem cells." Science, 309:1369.
  11. ^ Irina Klimanskaya, Young Chung, Sandy Becker, Shi-Jiang Lu & Robert Lanza. (August 23, 2006) "Human embryonic stem cell lines derived from single blastomeres." Nature. doi:10.1038.
  12. ^ Takahashi K and Yamanaka S. "Induction of Pluripotent Stem Cells from Mouse Embryonic and Adult Fibroblast Cultures by Defined Factors". Cell. 126: 663–676.
  13. ^ Nerensini, F. (2000) "And Man Descended from the Sheep: The Public Debate on Cloning in the Italian Press." Public Understanding of Science, vol. 9, pp.359-382.
  14. ^ Nisbet, M.C., Brossard, D. & Kroepsch, A. (2003) "Framing Science: The Stem Cell Controversy in an Age of Press/Politics." The Harvard International Journal of Press/Politics. Vol. 8, No. 2, pp. 36-70 DOI: 10.1177/1081180X02251047.
  15. ^ Tilghman,Shirley M. (November 11, 2004) "Address to the Stem Cell Institute of New Jersey," Retrieved August 22, 2006.
  16. ^ Amos, Jonathan. (September 5, 2005) "Winston warns of stem cell 'hype'." BBC News. Retrieved August 14, 2006.
  17. ^ Wade, Nicholas. (August 14, 2006) "Some Scientists See Shift in Stem Cell Hopes." New York Times. Retrieved August 15, 2006.
  18. ^ Lori B. Andrews et al. (March 19, 2002)."Open Letter to US Senators on Human Cloning and Eugenic Engineering." Retrieved on August 7, 2006
  19. ^ Jeremy Rifkin. (February 18, 2002). "Fusion Biopolitics." The Nation. Retrieved on August 7, 2006.
  20. ^ "'IVF Treatment killed my daughter.'" (June 30, 2005). BBC News. "UK woman killed by rare IVF risk." (April 13, 2005). BBC News. Retrieved August 7, 2006.
  21. ^ Committee on Guidelines for Human Embryonic Stem Cell Research. (April 26, 2005). "Guidelines for Human Embryonic Stem Cell Research." National Academies Press. Retrieved August 7, 2006.
  22. ^ California Institute for Regenerative Medicine. (August 2, 2006). "Final Compiled Proposed CIRM MES Regulations." Retrieved August 7, 2006.
  23. ^ "Scientists seek simple remedies to cloning conundrums". (May 2005). Nature Medicine. p. 459.
  24. ^ Denise Gellene. (May 10, 2002). "Clone Profit? Unlikely: The Technology’s Commercial Viability Faces Many Hurdles." Los Angeles Times.
  25. ^ Regalado, Antonio, David P. Hamilton (July 2006). "How a University's Patents May Limit Stem-Cell Researcher." Wall Street Journal. Retrieved on July 24, 2006.
  26. ^ Kintisch, Eli (July 18, 2006) "Groups Target Stem Cell Patents." ScienceNOW Daily News. Retreived August 15, 2006.
  27. ^ Associated Press. (July 19, 2006) "Stem Cell Patents Come Under Fire." Retrieved August 15, 2006.
  28. ^ ""President Clinton's Comments on NIH and Human Embryo Research"". U.S. National Archives. Retrieved July 19, 2006. {{cite web}}: Unknown parameter |creationdate= ignored (help)
  29. ^ Connolly, Ceci (2005). ""Despite Bush Veto, Stem Cell Research Abounds"". Washington Post: A01. Retrieved July 21, 2006. {{cite journal}}: Cite has empty unknown parameter: |coauthors= (help); Unknown parameter |date of work= ignored (help); Unknown parameter |month= ignored (help)
  30. ^ Kellman, Laurie. ""Senate Approves Embryo Stem Cell Bill"". Associated Press. Retrieved July 18, 2006. {{cite web}}: Unknown parameter |date of work= ignored (help)
  31. ^ Gail H. Javitt, Kristen Suthers, Kathy Hudson. (April 2005) "Cloning: A Policy Analysis." Genetics and Public Policy Center. Retrieved September 25, 2006.
  32. ^ Gledhill, Lynda (2006-07-21). "Governor OKs stem cell research funds Schwarzenegger authorizes loans for $150 million". San Francisco Chronicle. pp. B-1. Retrieved 2006-07-29. {{cite news}}: Cite has empty unknown parameter: |coauthors= (help)
  • Nisbet, M.C. (2004). The Polls: Public opinion about stem cell research and human cloning. Public Opinion Quarterly, 68 (1), 132-155 [34]
  • Nisbet, M.C. (2005). The competition for worldviews: Values, information, and public support for stem cell research. International Journal of Public Opinion Research, 17, 1, 90-112 [35]
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