Use of Human Embryos
Objections to the Use of Human Embryos for Stem Cell Research
Russell W. Carlson
Department of Biochemsitry & Molecular Biology
Technical Director of the Complex Carbohydrate Research Center
University of Georgia
Presented to the Christian Faculty Forum
March 27, 2002
Public Policy Objections
Summary & Final Thoughts
April 4, 2002 Criticisms of adult stem cell pluripotency
July 4, 2002 Nature article on adult stem cell pluripotency
One of the purposes of science, perhaps the main purpose (at least in my mind), is to understand nature and to apply that understanding in a manner that benefits society. Therefore, when new technical advances are made through basic research, society is often faced with the decision of how those advances can be used for beneficial purposes. During this decision making process, it is often necessary to determine what is ultimately beneficial; i.e. which uses of a new technology maximize the benefits and minimize the risks. Perhaps the development of nuclear energy technology is a good example of how these decisions are made. What uses of nuclear energy are beneficial? What are the risks? Can further research make nuclear technology more beneficial and less risky? Ethical concerns surround many of these decisions. These concerns address what we, as human beings, ought to do; what is the right (i.e. "good") way, or wrong (i.e. "bad") way, to use a new technology. These decisions are based on a variety of reasons; they are made, sometimes in secret, for national security reasons, by legislation after public debate, or, possibly, for reasons of profit, etc. Sometimes these decisions are altered by public protest. As we know, the debate over nuclear energy technology continues to the present time and the decisions reached vary from one country to another.
Stem cell technology, like nuclear energy technology, promises great benefits to society; the curing or treatment of many diseases. Also, like nuclear energy technology, stem cell technology requires decisions of what we ought to do; what are the right or wrong ways of using this technology. However, the use of human embryos for stem cell research or therapeutic purposes addresses a deeper question. It addresses the question, not only of what we ought or ought not do, but of who we are. Is there some intrinsic, measureless, basic "value" in a human individual that encompasses all stages of development, from conception to death? Or, is the "value" of a human individual entirely variable during development, ranging from "(genetic) material" at conception to human being at (when???). How one views the use of human embryos for research depends on how one answer's to these questions.
The debate over the use of embryos for stem cell research made the cover of Newsweek last July (2001). The cover page featured a picture of embryonic stem cells with the headlines, "The Stem Cell Wars", "Embryo research vs. pro-life politics", "There's hope for Alzheimer's, heart disease, Parkinson's, and diabetes", "But will Bush cut off the money?". The way these questions are phrased and positioned illustrates an unfortunate bias that masks the profound questions that need to be addressed regarding the use of human embryos for research or therapeutic applications. If you're pro-life then you are just playing politics that are preventing cures for Parkinson's, Alzheimers, heart disease, and diabetes, and you should, without thinking, be opposed to using human embryos for stem-cell research. Of course, by implication, if you support abortion rights then you should, again without thinking, be in favor of using embryos for stem cell research. Also, if you happen to be a Bush supporter, you are also preventing such cures, and, again, you should automatically be opposed to the use of embryos for stem cell research; and vice-versa. Such politicization only impedes a serious discussion of the serious ethical, scientific, and public policy problems that exist with the use of human embryos for this type of research. There are serious objections on all three fronts.
Before going further with this discussion, it probably is necessary to define the stem cell. Basically, in our body we have many different types of cells; skin cells, blood cells, nerve cells, liver cells, etc. These cells are developmentally arrested in the sense that a liver cell will always remain a liver cell; it can't become a skin cell, etc. Such cells are called somatic cells. On the other hand, there must be a developmental source for these somatic cells. This source is the stem cell, a cell that can give rise to different cell types (i.e. different tissues and organs). It is this ability of the stem cell which gives it great medical potential for treatment of various diseases through the regeneration of various tissues; e.g. nerve cells, dopamine-generating nerve cells (Parkinson's disease), insulin-generating cells, heart muscle cells, etc.
A brief description of stem cell research, its potential, the source of stem cells, and the role of embryos in this research can be found at the NIH WEB site www.nih.gov/news/stemcell/primer.htm. 1 A number of terms are used when describing stem cell research. These terms are totipotent, pluripotent, and multipotent. Development begins at conception with a fertilized egg. This fertilized egg is totipotent which means that it can develop into an individual human being. "Individual" should be stressed at this point since this how the development of each human person begins; of how "Joe", "Mary", your Dad, your child, your Mom, your wife, your husband, and how "you" began. Shortly after conception (about four days), the embryo exists as an inner layer of cells surrounded by an outer layer of cells. At this developmental stage the embryo is known as the blastocyst. The outer cell layer forms the tissues that support fetal development in the uterus such as the placenta. The inner cells will eventually give rise to every type of tissue found in the human body. Because of this ability, the inner cells are called pluripotent. These cells are not totipotent because it is stated that they can not, without the outer cell layer, produce the tissues required for fetal development. However, there is some evidence that these inner cells can also give rise to these outer layer cells which would, in essence, allow the regeneration of the embryo.2 The pluripotent cells give rise to more specialized stem cells, e.g. blood stem cells which give rise to red blood cells, white blood cells and platelets, but not (supposedly) to other tissue types. These specialized stem cells are called multipotent, and are commonly found in adults. Multipotent cells were thought not to be able to give rise to different tissue cell types. However, as will be discussed below, recent research has changed this view.
The source of embryonic stem cells (ES) is the embryo, or cells from the fetus (embryonic germ, EG, cells). The derivation of ES cells requires the destruction of the embryo, and EG cells are obtained from the aborted fetus. ES cell lines have been derived from "left-over" embryos from in vitro fertilization (IVF) clinics (with permission from the donors). Another potential method of obtaining ES cells is by a method called somatic nuclear cell transfer (SCNT). In this technique, also known as cloning, the nucleus of the egg cell is replaced by the nucleus of a somatic cell (e.g. skin cell, etc.). Once this is done, an embryo begins to develop. This embryo has the genetic make-up of the person from which the somatic cell (skin cell) was obtained. As with other ES cells, the ES cells from SCNT embryos are derived from the inner cells of the blastocyst stage of the embryo. Currently neither the use of human embryos for the production of stem cells, or the creation of embryos through cloning (i.e. SCNT) can be supported by public funding.
The main driving force for the promotion of stem cell research is the enormous potential to treat disease. Because of this potential, there is little, if any, disagreement with doing stem cell research. The disagreement comes, not with stem cell research, but with the source of the stem cells. For many, the deliberate destruction of the embryo to produce such cells is the destruction of human life and is, therefore, unacceptable. Other sources of stem cells such as those from (a.) adult tissues, or from the (b.) umbilical cord, pose no ethical problems; however, the various reports/recommendations from the National Bioethics Advisory Commission (NBAC), NIH, and American Academy for the Advancement of Science (AAAS) (and other organizations) state that adult stem cells have limited potential for forming different tissues, and that they are not as readily preserved or grown (i.e. expanded) in the laboratory as are ES stem cells. The main justifications given for using embryonic stem cells is that they are pluripotent, i.e. they can form many different types of tissue, and they can be preserved and grown under laboratory culture conditions.1-6 However, the use of adult stem cells to achieve the above goals would avoid the ethical problems of using ES cells. Basically, the scientific objection is this: if there is an alternative way (i.e. other than using ES cells) of doing stem cell research and therapy, then we have no business destroying human embryos. In fact in the NBAC, in their efforts to "respect the embryo as a form of human life" made the following recommendation:
"In our judgment, the derivation of stem cells from embryos remaining following infertility treatments is justifiable only if no less morally problematic alternatives are available for advancing the research. But as we have noted, ES cells from embryos appear to be different in scientifically important ways from AS cells and also appear to offer greater promise of therapeutic breakthroughs. The claim that there are alternatives to using stem cells derived from embryos is not, at the present time, supported scientifically. We recognize, however, that this is a matter that must be revisited continually as science advances" (p. 52 of the NABC report).5
Of course, the ability to treat human diseases with adult stem cell sources would meet this recommendation, and, also, dramatically reduce the funding prospects of ES cell research. Thus, in terms of the science, there is somewhat of a "contest" between ES cell research and adult stem cell research. The above NBAC recommendation was made in 1999. Perhaps it is time that this matter is "revisited".
The main reasons for using ES cells, as stated above, are: they can differentiate into many different types of tissues, and they can be preserved and grown under laboratory (in vitro) conditions. On the other hand, the validity of these reasons with regard to the treatment of disease are still uncertain as evidenced by the many qualifying words used in describing the potential therapeutic value of ES cells. For example:
"We know that embryonic stem cells can differentiate into any tissue of the human body; might they therefore also be able to treat diseases like Parkinson's, Alzheimer's and diabetes? In principle this ability to differentiate into blood, muscle or neural tissue may make embryonic stem cells the gold standard for replacing bad tissue with good. But some antiabortion advocates rankled that these cellular chameleons come from embryos, call for a categorical ban on funding this research."6
"….could produce new liver cells…" "…..might cure…." "….could replace cells damaged by…."7
"Because they have the dual ability to proliferate indefinitely and differentiate into multiple tissue types, human ES cells could potentially provide an unlimited supply of tissue for human transplantation. Though human ES cell-based transplantation therapy holds great promise to successfully treat a variety of diseases (e.g. Parkinson's disease, diabetes, and heart failure) many barriers remain in the way of successful clinical trials".8
What are the barriers (other than the ethical objections) for using human embryonic stem cells to treat disease? Many of these barriers are described in a recent review by Odorico, Kaufman, and Thomson.8 Thomson is the University of Wisconsin scientist who first cultured stem cells from human embryos.2 They are:
1. The human ES cells require "feeder" cells in order to be maintained and grown in culture. These "feeder" cells are mouse cells (fibroblasts) that provide the necessary (but unknown) factors required for growth. Thomson states that for any clinical use "it would be essential to establish feeder-independent culture conditions, which permit large-scale propagation of human ES cells in culture." Obviously, this is necessary to avoid contamination by the mouse cells during the treatment of any disease.
2. ES cells, in culture exist as a mixture of cells with different tissue types. Before they can be used, it is necessary to show that ES cells are capable of forming the particular cell type of interest and to purify that cell from the mixed population. This must be done since it is not feasible to inject a mixture of cell types (i.e. nerve, muscle, skin, etc.) in order to treat a specific tissue defect, e.g. to repair nerve damage.
3. It still needs to be shown that once the ES cells differentiate into the correct tissue type that they function in a normal manner.
4. Once this is all done, the experimental trials to actually treat a disease must be tested and proven safe and effective in an animal system.
5. Transplantation of ES cells may cause tumor formation since these cells may also contain small numbers of undifferentiated cells.
6. It will be necessary to prevent rejection of the introduced ES cells.
Two recent papers illustrate these barriers are serious problems. One paper describes work that involves human subjects and EG cells (e.g. ES cells from fetal tissue, not from embryos), and the other involves ES cells in a rat system. In the first paper9, C.R. Freed, P.E. Greene, R.E. Breeze et. al. show that these cells survived and grew into the right kinds of brain cells, but did not help patients older than 60. Younger patients improved somewhat, but only for one year. After that, in some of these patients, apparently too much dopamine was being produced resulting in uncontrollable writhing and jerking. (The exact quote is: "After improvement in the first year, dystonia and dyskinesias recurred in 15 percent of the patients who received transplants, even after reduction or discontinuation of the dose of levodopa".) Thus, these ES cells failed to function in a normal manner. In the second paper10 L.M. Bjorklund, R. Sanchez-Pernaute, S. Chung, et al. describe the results after ES cells were injected into 25 rats with Parkinson's. In 5 rats, the injected cells did not survive. In 14 rats the injected cells survived, dopamine was produced, and Parkinson's symptoms were alleviated. However, five rats had to be killed due to illness caused by tumor formation at the injection site. Obviously, tumor formation is a serious problem. Other work shows that gene expression in ES cells is unstable11, and that uniform singularly differentiated cells (e.g. only liver cells) have not been produced.12 These, and other, examples which demonstrate the above problems, or barriers, with using ES cells can be found at a number of WEB sites, one of which is www.stemcellresearch.org. Of course, such problems are normal in scientific research, and these investigators believe these barriers will be overcome by further research. In fact, one of the reasons they support Federal funding of ES cell research is so that the "barriers" to the use of ES cells can be overcome. However, why pursue this research in a system that raises such monumental ethical problems when there is evidence of a better system without the ethical problems; namely, using adult stem cells.
What about the use of adult stem cells? Are they, or can they be, as effective as ES cells? The July 9, 2001 Newsweek article (Cellular Divide)7 mentions the possibilities of adult stem cells for the treatment of disease. However, unlike the positive qualifying words promoting ES cell research, this time the qualifying words are negative, i.e. "….may not….", "….might not…." etc. The article goes on to give the opinions of several ES cell researchers: "….the studies on human adult stem cells may be flawed…", these studies are 'crap science', "No paper shows definitively any adult stem cell in humans turning into anything else", "It's baloney that adult stem cells are all we need to make regenerative medicine real", etc. Are these "critical" statements valid? Let's take a brief look at some recent work on adult stem cells:
1. "These adult bone marrow cells have tremendous differentiative capacity as they can also differentiate into epithelial cells of the liver, lung, GI tract, and skin. This finding may contribute to the clinical treatment of genetic disease or tissue repair." 13
2. Other work shows the production of liver cells from bone-marrow cells in humans.14,15
3. The treatment of damaged heart tissue has been reported using adult bone marrow-derived stem cells.16
4. Adult stem cells can be grown in culture and retain their ability to differentiate. "Reyes and colleagues show that nonhematopoietic primary bone marrow cells…grown in vitro for over a year, maintain the ability to differentiate in vitro into multiple cell types."17
5. Workers at the Stem Cell Institute at the University of Minnesota (under the direction of Catherine Verfaille) have found a very versatile adult stem cell. "A stem cell (from bone marrow) has been found in adults that can turn into every tissue in the body." "This cell is called the multipotent adult progenitor cell (MAPC), and may be as versatile as ES cells." "These cells seem to grow indefinitely in culture, like ES cells." "MAPCs can turn into a myriad of tissue types, muscle, cartilage, bone, liver, and different types of neurons and bran cells." "Unlike ES cells they do not seem to form cancerous masses if you inject them into adults."18
6. Adult stem cells can be isolated from skin that can differentiate into various cell types. Toma et al. state: "We describe here the isolation of stem cells from juvenile and adult rodent skin. These cells derive from the dermis and clones of individual cells can proliferate and differentiate in culture to produce neurons, glia, smooth muscle cells and adipocytes. Similar precursors that produce neuron-specific proteins upon differentiation can be isolated from adult human scalp. Because these cells generate both neural and mesodermal progeny, we propose that they represent a novel multipotent adult stem cell and suggest that skin may provide an accessible, autologous source of stem cells for transplantation."19
These are a few recent examples showing that adult stem cells can (1.) differentiate into many different tissues, probably just as many as ES cells, (2.) be grown in culture that are stable over pro-longed periods of time, (3.) do not cause tumor formation at grafting sites, and (4.) have actually been shown to function and have therapeutic value. Furthermore, the ability to introduce the patient's own stem cells as a treatment avoids problems of tissue rejection.
This work shows that the use of ES cells the has serious problems, and that stated goals given to justify the destruction of human IVF embryos for ES cell research can be met by using adult stem cells. The science does not support the destruction of human embryos in order to achieve the stated goals stem cell research. It will be interesting to see how serious the scientific community is with regard to the NBAC recommendation that "…the derivation of stem cells from embryos remaining following infertility treatments is justifiable only if no less morally problematic alternatives are available for advancing the research".
In the book The Human Embryonic Stem Cell Debate, Erik Parens (an Associate for Philosophical Studies at the Hastings Center, a bioethics think tank in Garrison, N.Y.) frames the basic ethical problem surrounding the use of human embryos in stem cell research as follows:
"The major argument for doing [human] embryo research is that it promises to reduce human suffering and promote well-being. The major argument against using human embryos for research is that they have the moral status of persons and thus should not be destroyed, no matter how great the human benefit."20
The National Bioethics Advisory Commission (NBAC) addressed the ethical problem as follows:
"Although we believe most would agree that human embryos deserve respect as a form of human life, disagreements arise regarding both what form such respect should take and what level of protection is required at different stages of embryonic development. Therefore, embryo research that is not therapeutic to the embryo is bound to raise serious concerns and to heighten the tensions between two important ethical commitments: to cure disease and to protect human life. For those who believe that the embryo has the moral status of a person from the moment of conception, research (or any other activity) that would destroy the embryo is considered wrong and should not take place. For those who believe otherwise, arriving at an ethically acceptable policy in this arena involves a complex balancing of a number of important ethical concerns."5
The NBAC goes on to give a series of eight recommendations in support of the use of EG and ES cells in research, and in support of Federal funding for the creation of ES cells from embryos. The justification for the destruction of embryos is based on a utilitarian view, a benefit verses risk assessment; the NBAC states:
"In our view, the ban conflicts with several of the ethical goals of medicine and related health disciplines, especially healing, prevention, and research. These goals are rightly characterized by the principles of beneficence and nonmaleficence, which jointly encourage pursuing social benefits and avoiding or ameliorating potential harm."5
While the wording is a bit different, both the AAAS and the NIH have the same utlilitarian viewpoint, tempered by the some notion that "embryos deserve respect as a form of human life".1,3,4
Obviously, as Parens states (see above), if the embryo has the status of a person, then it is wrong to destroy it for therapeutic or research purposes regardless of the potential the benefit. Thus, the views of the AAAS, the NIH, and the NBAC (as well and the National Academy of Sciences) that the embryo should be respected (as a form of human life) but also can be destroyed for stem cell research seem contradictory. What does this type of "respect" mean? What practical form does this "respect" take? This is answered in the recommendations made by the NBAC (which are similar to the NIH Guidelines).5 According to these guidelines, respect means: (a.) that ES cells should be derived only from embryos from IVF clinics that would otherwise be destroyed, (b.) that these embryos should only have been made for the purpose of becoming pregnant and should not be prepared specifically for research purposes, (c.) that embryos should not be made by SCNT, i.e. cloning, (d.) that that embryos should be destroyed only with good reason, e.g. for research that is necessary to develop cures for life-threatening or debilitating diseases, (e.) that they be destroyed only when there are "no less morally problematic alternatives available for advancing the research", and (f.) that embryos can not be sold before their destruction. (As described above with regard to adult stem cell research, there appears to be a far less morally problematic alternative available, yet, the push to support federal funding of ES cell research continues.) In a recent statement, the AAAS recommend the support of Federal funding, not only for the use of IVF "left over embryos", but also for the SCNT creation of embryos for stem cell research and therapeutics.21
The utilitarian view expressed by the NBAC, NIH, and AAAS for justifying the destruction of a human embryo is based on placing a variable value on human life; i.e. a "form of human life" (that can be destroyed and used as raw genetic material) at one end of the scale versus a "person" at the other end. Exactly how does one go about determining the relative value of a human life, and, further, how does one determine what "form of human life" is permissible to be destroyed, even for the supposed benefit of others? According to the NBAC embryos can have different moral statuses. Creating an embryo by IVF for the purposes of reproduction and subsequently destroying it to create ES cells (if it is not used for reproduction) is permitted while creating an embryo specifically for ES cell research (i.e. for the purpose of destruction for research) is not permitted (it does not show "respect"). In this instance, it is the motivation/intention, of those who make the embryo that determines its value or its moral status (this is discussed by Parens, see above reference). It's "respectful" to destroy an embryo (a "left over" embryo) if the motivation for creating it was "natural", i.e. for becoming pregnant. The destruction value point of the embryonic "form of human life" depends on the intent (and permission) of the parents.
At what point on the scale from a "form of human life" to a "person" should destruction be allowed? How is this point determined? Unfortunately, one could argue that the point of "personhood" is currently being defined by those who will be the beneficiaries of the definition. In a recent article in Slate22, William Saletin describes the Senate subcommittee testimony of Advanced Cell Technology (ACT) CEO Michael West, and ACT's ethicist Ronald Green (it is interesting that this company employs an "ethicist"-perhaps a more accurate description would be Public Relations Expert). They stated that it is permissible to destroy human embryos before 14 days since, before this time, the "primitive streak" has not formed and the embryo has not "decided" whether it will be one or two persons. Therefore, according to West and Green, the embryo is not an "individualized human being" before 14 days. This definition of an individual human being is, of course, extremely convenient for ACT. Apparently, as stated in the Slate article, "the argument (by West and Greene) is that since the early embryo could become one body or two bodies, maybe its nobody".
There is great danger in the notion that the value of human life is relative and can be determined by other individuals or by society. In the case of ES cell research the point at which a human life can be destroyed has been defined and justified by the potential medical benefits. In the recent past this point has been defined by race, or by religion, or mental capacity, etc., and has led to the destruction of millions of lives. In fact, at the present time the former leader of Yugoslavia, Milosovic, is being tried for contributing to the deaths of many people because their value (or lack thereof) was determined by their ethnicity. Do we really think our society is immune from sinking to such a level if we accept the premise of relative human value? One of the foremost bio-ethicists in the United States is Peter Singer. He is currently the Ira. W. DeCamp Professor of Bioethics in the University Center for Human Values, Princeton University. He writes23 the following with regard to infants:
"…… the fact that a being is a human being, in the sense of a member of the species Homo sapiens, is not relevant to the wrongness of killing it; it is, rather, characteristics like rationality, autonomy, and self-consciousness that make a difference. Infants lack these characteristics. Killing them, therefore, cannot be equated with killing normal human beings, or any other self-conscious beings. This conclusion is not limited to infants who, because of irreversible intellectual disabilities, will never be rational, self-conscious beings. We saw in our discussion of abortion that the potential of a fetus to become a rational, self-conscious being cannot count against killing it at a stage when it lacks these characteristics - not, that is, unless we are also prepared to count the value of rational self-conscious life as a reason against contraception and celibacy. No infant - disabled or not - has as strong a claim to life as beings capable of seeing themselves as distinct entities, existing over time."
"The difference between killing disabled and normal infants lies not in any supposed right to life that the latter has and the former lacks, but in other considerations about killing. Most obviously there is the difference that often exists in the attitudes of the parents. The birth of a child is usually a happy event for the parents. They have, nowadays, often planned for the child. The mother has carried it for nine months. From birth, a natural affection begins to bind the parents to it. So one important reason why it is normally a terrible thing to kill an infant is the effect the killing will have on its parents."
Peter Singer knows that the utilitarian view that the value of human life is relative does not just include the embryo and fetus, but logically extends to infants, and to adults (also described in this chapter from his book, Practical Ethics). Of course, not everyone who is in favor of using human embryos for ES cell research shares the views of Peter Singer. However, the rationale justifying the destruction of the human embryo (given by the NBAC, NIH, AAAS, NAS etc.) is the same as that given by Singer. For him, infants (not just embryos) are a "form of human life" that can be destroyed under some circumstances. These circumstances depend on the "attitude of the parents". Thus the value of the "form of human life" we know as an infant depends on the intentions of the parents. The language and logic of Peter Singer are essentially the same as those coming from the NIH, the NBAC, the NAS, and the AAAS that justify the destruction of the embryo for ES cell research. Peter Singer is simply more consistent with this philosophy than are these organizations. The view that the value of human life is relative and can be determined by us is a very slippery slope indeed; one on which a society can easily slide into the atrocities of Nazism, Stalinism, Pol-Pot-ism, etc. The slipperiness of this slope is the reason why German universities have denied a platform for Peter Singer. There is much to object to with the idea that we, any individual or government policy, can determine the value of a human life and when it can or cannot be destroyed. If one applies the benefit versus risk criterion, the risk is far too great.
Public Policy Objections
How do we, as a democratic society, determine a policy about whether there is some intrinsic, measureless, basic "value" in a human individual that encompasses all stages of development, from conception to death, or whether the "value" of a human individual is entirely variable during development, and, at some stage, is "valueless" enough to be destroyed for potentially beneficial purposes. Who determines this policy? Teachers? Preachers? Theologians? Psychologists? Scientists? Bio-ethicists?
In the case of ES cell research, decisions have been made by the usual governmental processes involving the President, House, and Senate. However, the major influence over these decision makers are the experts that are assembled to form advisory committees and prepare recommendations to these government bodies as well as other government agencies, such as the NIH. The panels advising the government decision makers concerning ES cell research have been the Advisory Committee to the Director (ACD) of the NIH (this is the committee that composed the NIH Stem Cell Guidelines), and the NBAC (which was commission by President Clinton in October of 1995). Both of these panels consisted largely of scientists, and clinicians, with a few Professors of Bioethics, Philosophy and Law. These panels did not have representatives from any of the major religious groups (i.e. minister, priest, or rabbi, etc.), nor any "average" citizen. Of course, both panels sought the opinions of many to assist them in forming their recommendations. But why should scientists be the major group comprising these panels? After all, ultimately, the question being decided is about how to view the value of a human life; no one disagrees with the stated goals and potential of ES cell research. This is not necessarily a question that needs to be addressed predominantly by scientists. Perhaps the panels should have been comprised of "average" citizens seeking the opinions of scientists, rather than of scientists seeking the opinions of citizens. In fact, one could argue that the make up of these panels demonstrates a very large conflict of interest since it is highly likely that the majority of these panel members were in favor of ES cell research and the derivation of more ES cell lines by destroying embryos before consulting anyone outside the panel. This problem is highlighted in a statement included in a Newsweek (July 9, 2001) article, A Question of Life or Death:
"When professional ethicists debate the shoulds or shouldn'ts of public policy, personal feelings carry no weight. Neither do appeals to Scriptures or other religious authority." "Even arguments of abstract moral principle, like whether noble ends ever justify ignoble means, must be tempered by considerations of concrete circumstances and probable outcomes."7
Why not consult the Scriptures and religious authority? After all, the Scriptures and religious authority are the foundations of almost all of the ethical values of millions of citizens in this country. Without considering the Scriptures or seeking the views of religious leaders, the decisions reached may alienate many citizens from science. It should be remembered that it is the public that funds all government research.
The basic objections, then, to how the public policy surrounding ES cell research is being formulated are: (a.) The panels formulating the recommendations are comprised of an elite group of largely scientists, and some other academic professionals and bioethicists. This group likely has a large conflict of interest influencing their recommendations. (b.) The recommendations to publicly fund the creation and destruction of human embryos for ES cell research may not reflect the view of millions of citizens and, in fact, may be very offensive to many; particularly with the advances in adult stem cell research which has no problematical ethical baggage.
Some Final Thoughts
The objections to ES cell research are summarized as follows:
1. In the area of science, current research is showing that the goals of ES cell research can be met by using adult stem cells. These scientific advances make the destruction of embryos unnecessary and according to the NBAC guidelines, if alternate methods are available, the use of human embryos for stem cell research should not be permitted.
2. In the area of ethics, ES cell research requires the destruction of the human embryo and this, in turn, requires a governmental policy decision that, in essence, declares that the value of human life is relative and that there is a point when it can be destroyed for potentially beneficial purposes. According the benefit versus risk criteria for supporting or not supporting ES cell research, the risk to society is far greater than any possible benefits.
3. In the area of public policy, the panels assembled to study and make recommendations to the President, Congress, and government agencies (e.g. the NIH) are comprised mostly of scientists, clinicians and other professionals whose conclusions may be strongly influenced by conflicts of interest. In addition this may lead to government policies which offend a great many people whose support is needed for government funded scientific research.
While objections in the area of science and public policy are serious, the critical objection is that ES cell research implies government acceptance and support of the view that the value of human life is relative, that at some point it can be sacrificed and used as raw material. Furthermore, to support ES cell research implies that certain members of our society and the government can determine when a human life is a person or not a person and can be sacrificed. In The Human Embryonic Stem Cell Debate, Gilbert Meilaender quotes a passage from Karl Barth (a highly respected 20th century theologian): "No community, whether family, village or state, is really strong if it will not carry its weak and even its very weakest members".24 Meilaender points out that the embryo is "the weakest and least advantaged of our fellow human beings".
The concept of the relative value of human life is based on the idea that a human life is a person when he/she has certain capabilities or characteristics; e.g. "characteristics like rationality, autonomy, and self-consciousness" as stated by Peter Singer. However, Meilander points out that, in Christian thought, there is an older concept of personhood, one that does not require some minimal set of capabilities or characteristics. This view (which is Meilander attributes to the Anglican theologian, Oliver O'Donovan) is that "a person is simply a 'someone who'-a someone who has a history." He goes on to state:
"That story [i.e. a personal history], begins before we are conscious of it and, for many of us, may continue after we have lost consciousness of it. It is nonetheless our personal history even when we lack awareness of it, even when we lack or have lost certain capacities characteristic of the species. Each story is the story of 'someone who', as a living human being, has a history".24
Christianity teaches that we are a human person, not because of what we can accomplish or because of our mental capacities, etc., but because we are made in the image of God and because we are so important to Him, that Christ died so that we can be reconciled with Him.
Lastly, in deciding the ethical issues of a new technology, we must decide what defines the "ethical line" that should not be crossed. Often, it seems that this "line" is determined, not by sound discussion of the ethical issues involved, but by whether or not it is technically feasible and potentially beneficial. Meilaender quotes the Mennonite theologian, John Howard Yoder:
"I am less likely to look for a saving solution if I have told myself beforehand that there can be none, or have made advance provision for an easy brutal one".
ES cell research offered a sort of "saving solution" to many diseases, and, initially at least, it seemed the easier, though more "brutal", route than that of looking for other solutions such as adult stem cell approaches. Because of this, the "ethical line" was drawn (by the NBAC, NIH, AAAS, NAS, etc.) that would allow the destruction of the human embryo by classifying it as a "form of human life" but not a person. This ethical line need not have been crossed. It was done, because it was, at the time, the perceived easy way to the "saving solution". The scientific community is creative enough find solutions that do not cross sensitive ethical lines. They need not settle for the less creative, easier more "brutal" route. However, there may be times when we may have to choose, for sound ethical reasons, to deny ourselves the benefits of a technical advance. It is up to us to rule technology, technology should not rule us. The technology of ES cell research is an example of, as Meilaender relates, "the human will, seeing a desired end, takes control, subjecting to its desire even the living human organism". He then reminds us of a warning given by C.S. Lewis in The Abolition of Man:
"We reduce things to mere Nature in order that we may 'conquer' them. We are always conquering Nature, because 'Nature' is the name for what we have to some extent conquered. The price of conquest is to treat a thing as mere Nature…The stars do not become Nature till we can weigh and measure them: the soul does not become Nature till we can psycho-analyze her. The wresting of the powers from Nature is also the surrendering of things to Nature. As long as this process stops short of the final stage we may well hold that the gain outweighs the loss. But as soon as we take the final step of reducing our own species to the level of mere Nature, the whole process is stultified, for this time the being who stood to gain and the being who has been sacrificed are one and the same. This is one of the many instances where to carry a principle to what seems its logical conclusion produces absurdity. It is like the famous Irishman who found that a certain kind of stove reduced his fuel bill by half and thence concluded that two stoves of the same kind would enable him to warm his house with no fuel at all. .. If man chooses to treat himself as raw material, raw material he will be."
April 4, 2002:
Three articles in Nature26,27,28 appeared that question the validity of the reports that AS cells can differentiate into different tissue types (i.e. known as transdifferentiation). Basically these Nature articles state that that the transdifferentiation of AS cells is not actual; that it is an artifact produced by fusion of the AS cell with the cell of a specific tissue, e.g. a liver cell. The experiments described in these Nature articles show that AS cells can fuse with ES cells resulting in a fused cell that has twice the number of chromosomes. Therefore, these authors state that the reported transdifferentiation of an AS cell is due to a fused cell that only gives the appearance that an AS cell has transdifferentiated. These reports are unfortunate; not because of the results, but because the authors designed "straw man" experiments for the purpose of discrediting the AS cell work. None of the AS cell experiments used ES cells, and no experiments were performed or described by the authors (or others) of these Nature articles which show that the results ascribed to the AS cell transdifferentiation were the actually due to cell fusion. In fact, at least one of the workers describing AS cell transdifferentiation, Diane Krauss of Yale University, stated that her transdifferentiated AS cells contained the normal number of chromosomes.29 Also, the reported medical benefits of AS cells (see examples above) still occur whether or not AS cells fuse with other cells.29 The ability of ES cells to fuse with AS cells may, in fact, prove to be another barrier to the therapeutic use of ES cells.
July 4, 2002
In an article that appeared in Nature30, it was reported that mesenchymal stem cells from adult marrow are pluripotent. These cells were able to differentiate into many different tissue types, and since they "proliferate extensively without obvious senescence or loss of differentiation potential, they may be an ideal cell source of therapy of inherited or degenerative diseases". In addition, this article directly contradicts the above claims that the ability of adult stem cells to differentiate into many tissues is due to an artifact of the experiment.
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