The stem cell controversy is the ethical debate primarily concerning the creation, treatment, and destruction of human embryos incident to research involving embryonic stem cells. Not all stem cell research involves the creation, use, or destruction of human embryos. For example, adult stem cells, amniotic stem cells and induced pluripotent stem cells do not involve human embryos at all.
Since stem cells have the ability to differentiate into any type of cell, they offer something in the development of medical treatments for a wide range of conditions. Treatments that have been proposed include treatment for physical trauma, degenerative conditions, and genetic diseases (in combination with gene therapy). Yet further treatments using stem cells could potentially be developed thanks to their ability to repair extensive tissue damage.
Great levels of success and potential have been shown from research using adult stem cells. In early 2009, the FDA approved the first human clinical trials using embryonic stem cells. Embryonic stem cells are totipotent, and thus can become any other cell type. Adult stem cells, however, are generally limited to differentiating into different cell types of their tissue of origin. However, some evidence suggests that adult stem cell plasticity may exist, increasing the number of cell types a given adult stem cell can become. In addition, embryonic stem cells are considered more useful for nervous system therapies, because researchers have struggled to identify and isolate neural progenitors from adult tissues. Embryonic stem cells, however, might be rejected by the immune system - a problem which wouldn't occur if the patient received his or her own stem cells.
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 a human embryo.
Some believe that human skin cells can be coaxed to "de-differentiate" and revert to an embryonic state. Researchers at Harvard University, led by Kevin Eggan, have attempted to transfer the nucleus of a somatic cell into an existing embryonic stem cell, thus creating a new stem cell line. Another study published in August 2006 also indicates that differentiated cells can be reprogrammed to an embryonic-like state by introducing four specific factors, resulting in induced pluripotent stem cells.
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. At the 2007 meeting of the International Society for Stem Cell Research (ISSCR), Lanza announced that his team had succeeded in producing three new stem cell lines without destroying the parent embryos. "These are the first human embryonic cell lines in existence that didn't result from the destruction of an embryo." Lanza is currently in discussions with the National Institutes of Health (NIH) to determine whether the new technique sidesteps U.S. restrictions on federal funding for ES cell research.
Anthony Atala of Wake Forest University says that the fluid surrounding the fetus has been found to contain stem cells that, when utilized correctly, "can be differentiated towards cell types such as fat, bone, muscle, blood vessel, nerve and liver cells". The extraction of this fluid is not thought to harm the fetus in any way. He hopes "that these cells will provide a valuable resource for tissue repair and for engineered organs as well".
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 are concerned with the rights and status of the embryo as an early-aged human life. They can believe that embryonic stem cell research instrumentalizes and violates the
sanctity of life and some also view it as tantamount to
murder. The fundamental assertion of those who oppose embryonic stem cell research is the belief that human life is
inviolable, combined with the belief that human life begins when a sperm cell fertilizes an egg cell to form a single cell.
A portion of 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 to be destroyed, or stored for long periods of time, long past their viable storage life. In the United States alone, there have been estimates of at least 400,000 such embryos. This has led some opponents of abortion, such as Utah Senator Orrin Hatch, to support human embryonic stem cell research. See Also Embryo donation.
Medical researchers widely submit 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 a variety of diseases and impairments. Spinal cord injuries and Parkinson's disease are two examples that have been championed by high-profile media personalities (for instance, Christopher Reeve and Michael J. Fox, who have lived with these conditions, respectively). The anticipated medical benefits of stem cell research add urgency to the debates, which has been appealed to by proponents of embryonic stem cell research.
In August 2000, The U.S. National Institutes of Health's Guidelines stated:
"...research involving human pluripotent stem cells...promises new treatments and possible cures for many debilitating diseases and injuries, including Parkinson's disease, diabetes, heart disease, multiple sclerosis, burns and spinal cord injuries. The NIH believes the potential medical benefits of human pluripotent stem cell technology are compelling and worthy of pursuit in accordance with appropriate ethical standards."
In 2006, researchers at Advanced Cell Technology of Worcester, Massachusetts, succeeded in obtaining stem cells from mouse embryos without destroying the embryos. If this technique and its reliability are improved, it would alleviate some of the ethical concerns related to embryonic stem cell research.
Another technique announced in 2007 may also defuse the longstanding debate and controversy. Research teams in the United States and Japan have developed a simple and cost effective method of reprogramming human skin cells to function much like embryonic stem cells by introducing artificial viruses. While extracting and cloning stem cells is complex and extremely expensive, the newly discovered method of reprogramming cells is much cheaper. However, the technique may disrupt the DNA in the new stem cells, resulting in damaged and cancerous tissue. More research will be required before non-cancerous stem cells can be created.
Update article to include 2009/2010 current stem cell usages in clinical trials. The planned treatment trials will focus on the effects of oral lithium on neurological function in people with chronic spinal cord injury and those that have received umbilical cord blood mononuclear cell transplants to the spinal cord. The interest in these two treatments derives from recent reports indicating that umbilical cord blood stem cells may be beneficial for spinal cord injury and that lithium may promote regeneration and recovery of function after spinal cord injury. Both lithium and umbilical cord blood are widely available therapies that have long been used to treat diseases in humans.
Embryonic stem cells have the potential to grow indefinitely in a laboratory environment and can differentiate into almost all types of bodily tissue. This makes embryonic stem cells a prospect for
cellular therapies to treat a wide range of diseases.
This argument often goes hand-in-hand with the
utilitarian argument, and can be presented in several forms:
Embryos are not equivalent to human life while they are still incapable of surviving outside the womb (i.e. they only have the potential for life).
More than a third of zygotes do not implant after conception. Thus, far more embryos are lost due to chance than are proposed to be used for embryonic stem cell research or treatments.
Blastocysts are a cluster of human cells that have not differentiated into distinct organ tissue; making cells of the inner cell mass no more "human" than a skin cell.
Some parties contend that embryos are not humans, believing that the life of ''Homo sapiens'' only begins when the heartbeat develops, which is during the 5th week of pregnancy, or when the brain begins developing activity, which has been detected at 54 days after conception.
In vitro fertilization (IVF) generates large numbers of unused embryos (e.g. 70,000 in Australia alone). Many of these thousands of IVF embryos are slated for destruction. Using them for scientific research uses a resource that would otherwise be wasted.
While the destruction of human embryos is required to establish a stem cell line, no new embryos have to be destroyed to work with existing stem cell lines. It would be wasteful not to continue to make use of these cell lines as a resource.
Abortions are legal in many countries and jurisdictions. The argument then follows that if these embryos are being destroyed anyway, why not use them for stem cell research or treatments?
This is usually presented as a counter-argument to using adult stem cells as an alternative that doesn't involve embryonic destruction.
Embryonic stem cells make up a significant proportion of a developing embryo, while adult stem cells exist as minor populations within a mature individual (e.g. in every 1,000 cells of the bone marrow, only 1 will be a usable stem cell). Thus, embryonic stem cells are likely to be easier to isolate and grow ex vivo than adult stem cells.
Embryonic stem cells divide more rapidly than adult stem cells, potentially making it easier to generate large numbers of cells for therapeutic means. In contrast, adult stem cell might not divide fast enough to offer immediate treatment.
Embryonic stem cells have greater plasticity, potentially allowing them to treat a wider range of diseases.
Adult stem cells from the patient's own body might not be effective in treatment of genetic disorders. Allogeneic embryonic stem cell transplantation (i.e. from a healthy donor) may be more practical in these cases than gene therapy of a patient's own cell.
DNA abnormalities found in adult stem cells that are caused by toxins and sunlight may make them poorly suited for treatment.
Embryonic stem cells have been shown to be effective in treating heart damage in mice.
Embryonic stem cells have the potential to cure chronic and degenerative diseases which current medicine has been unable to effectively treat.
Before the
primitive streak is formed when the embryo attaches to the uterus at approximately 14 days after fertilization, a single fertilized egg can split in two to form
identical twins, or a pair of embryos that would have resulted in
fraternal twins can fuse together and develop into one person (a
tetragametic chimera). Since a fertilized egg has the potential to be two individuals or half of one, some believe it can only be considered a ''potential'' person, not an actual one. Those who subscribe to this belief then hold that destroying a blastocyst for embryonic stem cells is ethical.
Viability is another standard under which embryos and fetuses have been regarded as human lives. In the United States, the 1973
Supreme Court case of ''
Roe v. Wade'' concluded that
viability determined the permissibility of
abortions performed for reasons other than the protection of the woman's health, defining ''viability'' as the point at which a fetus is "potentially able to live outside the mother's womb, albeit with artificial aid." The point of viability was 24 to 28 weeks when the case was decided and has since moved to about 22 weeks due to advancement in medical technology. Embryos used in medical research for stem cells are well below development that would enable viability.
In the US, only private funded companies are allowed to perform research on human embryonic or fetal stem cells. This fact "precipitates several immediate concerns.". Michele Garfinkel Publicly funded researchers adhere to ethic guidelines, but with private entities guidelines can become blurry. Another concern is since the research is funded privately, who in the public domain can benefit from these new private findings? Just as insurance is only available to those who pay the premium.
Many questions arise of this concern, Julian Savulescu lists several arguments.
It is liable to abuse. It violates a person's right to individuality, autonomy, self-hood. It allows eugenic selection.
His journal goes into details of the advantages of using stem cell lines mainly for therapeutic reasons with great emphasis on control. The main reason is that if this regeneration practice goes un-check, there will be someone out there that will be "playing Gods."
This argument is used by opponents of embryonic destruction as well as researchers specializing in adult stem cell research.
Pro-life supporters often claim that the use of adult stem cells from sources such as umbilical cord blood has consistently produced more promising results than the use of embryonic stem cells. Furthermore, adult stem cell research may be able to make greater advances if less money and resources were channeled into embryonic stem cell research.
Embryonic stem cells have never produced therapies, (to date, adult stem cells have been used in treatment) Moreover, there have been many advances in adult stem cell research, including a recent study where pluripotent adult stem cells were manufactured from differentiated fibroblast by the addition of specific transcription factors. Newly created stem cells were developed into an embryo and were integrated into newborn mouse tissues, analogous to the properties of embryonic stem cells.
This argument remains hotly debated on both sides. Those critical of embryonic stem cell research point to a current lack of practical treatments, while supporters argue that advances will come with more time and that breakthroughs cannot be predicted.
The main ethical theories used by opponents and supporters in this controversy are consequentialism (utilitarianism) and deontological ethics. Consequentialism is the ethical theory that assess the rightness or wrongness of a certain action based on the desirability of the results or the consequences of the action. In this theory good actions are actions that brings happiness or pleasure to the largest number of people. Unlike consequentialism, deontological ethics primary concern is the action in its self. The word Deon is a Greek word that means duty or obligation. This ethical theory judges the wrongness or rightness of an action based on the conformity of that action with certain norms or principals.
Immanuel Kant, a German philosopher expressed his deontological theory using the categorical imperatives. These categorical imperatives are principles that serve to guide the conduct of people. One of Kant’s categorical imperatives says, “always treat persons as ends in themselves and not merely as means to some other end.” If we give to the human embryo the moral status of a person, then under this principle it will be wrong to destroy the human embryo to save the lives of others.
Austria,
France,
Germany,
Ireland, do not allow the production of embryonic stem cell lines, but the creation of embryonic stem cell lines is permitted in
Finland,
Greece, the
Netherlands,
Sweden,
Italy and the
United Kingdom.
In 1973,
Roe v. Wade legalized abortion in the United States. Five years later, the first successful human ''in vitro'' fertilization resulted in the birth of
Louise Brown in England. 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 administration of President
Bill Clinton 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, 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 Bill Clinton) which prohibited any federal funding for the Department of Health and Human Services be used for research that resulted in the destruction of an embryo regardless of the source of that embryo.
In 1998, privately funded research led to the breakthrough discovery of Human Embryonic Stem Cells (hESC). 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. Though embryo destruction had been inevitable in the process of harvesting hESC in the past (this is no longer the case), the Clinton Administration had 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 George W. Bush administration which decided to reconsider the issue.
President Bush announced, on August 9, 2001 that federal funds, for the first time, would be made available for hESC research. However, the Bush Administration chose to limit taxpayer funding to then-existing hESC cell lines, thereby limiting federal funding to research in which "the life-and-death decision has already been made". 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. Public and private funding of research on adult and cord blood stem cells is unrestricted.
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. On July 18, 2006, the Senate passed three different bills concerning stem cell research. The Senate passed the first bill (Stem Cell Research Enhancement Act), 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. 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.
In 2005 and 2007, Congressman Ron Paul introduced the Cures Can Be Found Act, with 10 cosponsors. With an income tax credit, the bill favors research upon non embryonic stem cells obtained from placentas, umbilical cord blood, amniotic fluid, humans after birth, or unborn human offspring who died of natural causes; the bill was referred to committee. Paul argued that hESC research is outside of federal jurisdiction either to ban or to subsidize.
Bush vetoed another bill, the Stem Cell Research Enhancement Act of 2007, which would have amended the Public Health Service Act to provide for human embryonic stem cell research. The bill passed the Senate on April 11 by a vote of 63-34, then passed the House on June 7 by a vote of 247-176. President Bush vetoed the bill on July 19, 2007.
On March 9, 2009, President Obama removed the restriction on federal funding for newer stem cell lines.
Two days after Obama removed the restriction, the President then signed the Omnibus Appropriations Act of 2009, which still contained the long-standing Dickey-Wicker provision which bans federal funding of "research in which a human embryo or embryos are destroyed, discarded, or knowingly subjected to risk of injury or death;" the Congressional provision effectively prevents federal funding being used to create new stem cell lines by many of the known methods. So, while scientists might not be free to create new lines with federal funding, President Obama's policy allows the potential of applying for such funding into research involving the hundreds of existing stem cell lines as well as any further lines created using private funds or state-level funding. The ability to apply for federal funding for stem cell lines created in the private sector is a significant expansion of options over the limits imposed by President Bush, who restricted funding to the 21 viable stem cell lines that were created before he announced his decision in 2001.
The ethical concerns raised during Clinton's time in office continue to restrict hESC research and dozens of stem cell lines have been excluded from funding, now by judgment of an administrative office rather than Presidential or legislative discretion.
In 2005 the NIH funded $607 million worth of stem cell research, of which $39 million was specifically used for hESC.
Sigrid Fry-Revere has argued that private organizations, not the federal government, should provide funding for stem-cell research, so that shifts in public opinion and government policy would not bring valuable scientific research to a grinding halt.
In 2005 the State of California took out 3 billion dollars in bond loans to fund embryonic stem cell research in that state.
China has one of the most permissive human embryonic stem cell policies in the world. In the absence of a public controversy, human embryo stem cell research is supported by policies that allow the use of human embryos and therapeutic cloning. Iran has banned embryonic stem cell lines.
The
Southern Baptist Convention opposes human embryonic stem cell research on the grounds that "Bible teaches that human beings are made in the image and likeness of God (Gen. 1:27; 9:6) and protectable human life begins at fertilization." However, it supports adult stem cell research as it does "not require the destruction of embryos."
In regards, to
embryonic stem cell research, the
United Methodist Church stands in "opposition to the creation of embryos for the sake of research" as "a human
embryo, even at its earliest stages, commands our reverence." However, it supports
adult stem cell research, stating that there are "few moral questions" raised by this issue.
“The First Presidency of The Church of Jesus Christ of Latter-day Saints has not taken a position regarding the use of embryonic stem cells for research purposes. The absence of a position should not be interpreted as support for or opposition to any other statement made by Church members, whether they are for or against embryonic stem cell research.”
Islam support most forms of stem cell research. Islam’s obligation towards knowledge coupled with its tradition towards not allowing surrogate parenting or embryo adoption, leads many Islamic scholars to believe that the Qur’an can be used to support stem cell research.
To analyze Islam’s stance towards stem cell research, once again the status of the embryo must be determined. In Chapter 23, verse 12-14 the Qur’an teaches:
"We created (khalaqna) man of an extraction of clay, then we sent him, a drop in a safe lodging, then We created of the drop a clot, then we created of the clot a tissue, then We created of the tissue bones, then we covered the bones in flesh; thereafter We produced it as another creature. So blessed be God, the best of creators!"
This passage has been interpreted to indicate that a fetus is perceived as a human life, only later on in the biological development because of the Qur’an’s use of the words “thereafter We produced him as another creature."
The Shari’ah makes a distinction between actual life and potential life, determining that actual life should be afforded more protection than potential life. Thus, under most interpretations of Islamic law, the embryo is not considered a person and the use of it for stem cell research does not violate Islamic law. Also, under this same line of analysis, stem cells from aborted fetuses would also be permitted if the abortion was performed before the fourth month of pregnancy.
Islamic law prohibits surrogate parenting, adoption and the adoption of human embryos due to the importance of determining a child’s true parentage and inheritance rights.12 This would free up any excess embryos for research purposes since under Islamic law, they could not be used by anyone but the couple who created them. The Washington based Islamic Institute stated, ”Under Islamic principle of the ‘purposes and higher causes of the Shari’ah (Islamic law), we believe it is a societal obligation to perform research on these extra embryos instead of discarding them.” Several Islamic scholars have also pointed out that cloning embryos for therapeutic uses would also be permitted.
Many Islamic scholars also point to the belief that all knowledge emanates from God and that as such, human beings have an obligation to use that knowledge to serve human society.15 Like Judaism, Islam places an obligation on its followers to seek out knowledge, scientific knowledge in particular, since it is a part of human nature as created by God. As stated by Dr. Abdulaziz Sachedina:
”The will of God” in the Koran has often been interpreted as the processes of nature uninterfered with by human action. Hence, in Islam, research on stem cells made possible by biotechnical intervention in the early stages of life is regarded as an act of faith in the ultimate will of God as the Giver of all life, as long as such an intervention is undertaken with the purpose of improving human health.
Thus, Islam’s obligation towards knowledge coupled with its tradition towards not allowing surrogate parenting or embryo adoption, leads many Islamic scholars to believe that the Qur’an can be used to support stem cell research.
According to Rabbi Levi Yitschak Halperin of the Institute for Science and Jewish Law in Jerusalem, embryonic stem cell research is permitted so long as it has not been implanted in the womb. Not only is it permitted, but research is encouraged, rather than wasting it.
Similarly, the sole Jewish majority state, Israel, permits research on embryonic stem cells.
Stem cell laws
Dickey-Wicker Amendment
Genetics Policy Institute
Stem Cell Research Enhancement Act
Stem cell research policy
Fetal tissue implant
Video: The Stem Cell Controversy January 18, 2006, Woodrow Wilson Center event featuring Robin Cook (novelist), William B. Hurlbut, and Michael D. West
The Hinxton Group: An International Consortium on Stem Cells, Ethics & Law
A Scientific-Industrial Complex? By Sigrid Fry-Revere
On the Personhood of Pre-implantation Embryos
Videos about Stem Cell Ethics and Controversy
Stem cell information for beginners
Stem cell research pros and cons
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