Taking the moral high road: why embryonic stem cell research should be strictly regulated.

• Author: Kollmann, Maite S.

1. INTRODUCTION

   Human embryonic stem cell (hESC) research has been one of the most discussed topics in bioethics during the last several years, and the conflicts associated with the hESC controversy are on the cutting edge of science, politics, law, bioethics, and religion. The central issue is the moral problem created by the destruction of the embryo, which until now, was inevitably connected to hESC research.

   Part II of this article illustrates the fundamentals of the controversy and the position taken by the United States government. Part III proposes a practical solution--the implementation of strict federal oversight of federal funding for hESC research while alternative research, mainly on adult stem cells, is advanced. Additionally, Germany's approach to hESC research serves as an example of another country's debate over hESC research. By explaining the considerations prevailing in Germany, which focuses primarily on human dignity, this article illustrates that the rejection of hESC research is based on valid ethical concerns associated with the destruction of human life. Further, this article exposes why simply labeling hESC research opponents as overzealous, religious conservatives is an oversimplification and not conducive to an informed debate. Part IV confronts and rebuts the criticism of those who believe in employing hESC research. Mainly, this part belies the notion that the United States is a leading nation in hESC research, thereby putting the economic argument in favor of hESC research to rest. Finally, the benefits of cord blood banking are discussed as an alternative ethical means for exploring the eventual benefits of stem cell treatments.

   Accordingly, the aim of this article is two-fold: (1) to show, discuss, and compare two different approaches to a central bioethical question of modern times, hESC research, and (2) to propose a specific solution as to how the United States should deal with hESC research.

2. AN ANALYSIS OF HUMAN EMBRYONIC STEM CELL (hESC) RESEARCH IN THE UNITED STATES

   1. What Are Stem Cells and Why Is There a Controversy?

      The term "cell" originates from the Latin word "celia," which means "small room." (1) Stem cells are found "in embryos, in the fetus, the placenta and umbilical cord, and in parts of the body." (2) Stem cells are distinguished from other cell types by two important characteristics. First, they are unspecialized cells capable of renewing themselves through cell division, even after long periods of inactivity lasting as long as the human or animal is alive. (3) Second, under certain physiologic or experimental conditions, they can be induced to become tissue or organ-specific cells with special functions. (4) Because of these characteristics, stem cells offer the prospect of growing new tissue, repairing parts of the body damaged by accident or ill health, or treating a wide range of diseases that have developed because of a degeneration of cells, e.g., Type 1 Diabetes, Parkinson's disease, and Alzheimer's disease. (5)

      In 1981, scientists first discovered ways to derive embryonic stem cells from early mouse embryos. (6) On November 6, 1998, James Thomson, a professor at the University of Wisconsin, announced the discovery of a method to extract stem cells from human embryos and grow them in laboratories. (7) The resulting cells are called human embryonic stem cells (hESCs). (8) HESCs are derived from a group of cells called the inner cell mass, which is part of the early (four to five-day) embryo called the blastocyst. (9) Once removed from the blastocyst, the cells of the inner cell mass can be cultured into embryonic stem cells. (10) The process of cultivation typically requires the destruction of the human embryo. (11) HESCs are usually extracted from embryos created for reproductive purposes through in vitro fertilization. (12) Some excess embryonic stem cells that are not used during in vitro fertilization are donated for stem cell research with the informed consent of the donor. (13) So far, research has not developed a method that allows the extraction of embryonic stem cells without destroying the embryo. (14)

      The other type of stem cells that scientists have worked with is "somatic" or "adult" stem cells. (15) The primary roles of adult stem cells in a living organism are to maintain and repair the tissue in which they are found. (16) Human adult stem cells (hASCs) are present in many organs and tissues, including brain, bone marrow, peripheral blood, blood vessels, skeletal muscle, skin, teeth, heart, gut, liver, ovarian epithelium, placenta, testis, and umbilical cord. (17) HASCs may remain quiescent (non-dividing) for long periods of time or until there is a demand for the development of more cells. (18) There are only a small number of hASCs in each tissue; once removed from the body, their capacity to divide is limited, making the generation of large quantities of stem cells difficult. (19) In sharp contrast to hESCs, hASCs typically generate only cell types of the cell tissue in which they reside, meaning that they lack pluripotency (the ability to become any kind of cell). (20) Pluripotency is the trait that makes hESCs so highly desirable. (21)

      However, experiments over the last several years have tended to show that even hASCs may have pluripotent abilities. (22) It is important to note that scientists believe that tissues derived from embryonic and adult stem cells may differ in their likelihood of being rejected after transplantation. (23) HASCs, and tissues derived from them, are currently believed less likely to initiate rejection after transplantation because a patient's own cells could be expanded in culture, coaxed into assuming a specific cell type, and then reintroduced into the patient. (24) The ability to avoid rejection represents a significant advantage; an immune rejection can be circumvented only by continuous administration of immunosuppressive drugs, which may cause deleterious side effects. (25) Another major benefit of using hASCs is the decreased likelihood of cancerous development (26) because hASCs, unlike hESCs, do not "undergo uncontrolled transformation and growth." (27) Certainly, the single greatest advantage of hASCs over hESCs is that hASCs do not require the destruction of human life. (28)

      In sum, stem cell research poses many unresolved questions, but presents great potential for brilliant scientists to make exceptional breakthroughs for the benefit of mankind. The latest breakthrough, in 2006, was the discovery of conditions that allow the conversion of adult stem cells whereby the cells reassume their initial pluripotent status (iPSCs). (29) However, there remains a major risk in hESCs because of two factors. First, the active copies of the reprogramming genes remaining in the reprogrammed cells can trigger the occurrence of tumors. (30) Second, the retroviruses used to deliver the genes into cells' chromosomes may cause cancer if they connect to a gene that keeps cell division in check, thereby creating a disease in an attempt to cure another. (31)

      Currently, American law does not treat the legal status of unborn life uniformly. (32) The legal uncertainty adds to the fierce debate about the current practice of cultivating hESCs because cultivation requires the destruction of the human embryo. (33) From a neutral perspective, several approaches to the evolving moral issue are imaginable:

      First, opponents of hESC are often those who believe that the embryo has the moral status of a person from the moment of conception and that research (or any other activity) that would end the life of a person is wrong. (34) Former White House Press Secretary, Tony Snow, expressed this view when asked why President Bush vetoed federal funding for embryonic stem cell research: "[t]he simple answer is he thinks murder is wrong." (35) Snow later clarified that President Bush believes that human embryonic stem cell research involves "the destruction of human life." (36)

      Second, proponents of hESC research point out that in the natural reproductive process, human eggs are often fertilized but fail to implant in the uterus. (37) According to this standpoint, a fertilized egg has only the potential for human life, and cannot be considered equivalent to a human being until it has been successfully implanted into a woman's uterus. (38) Therefore, an early human embryo is merely a collection of cells with no strong moral status. (39) IR application, the cloning and embryonic stem cell research programs are noncontroversial because experimentation only destroys a lump of cells. Supporters of this argument attempt to bolster their pro-research position by emphasizing the medical potential of embryonic stem cell research. (40) However, the heart of the argument remains; a small group of cells has no moral status that needs to be considered. (41)

      Third, some propose an intermediary approach to hESC research and believe that the human embryo deserves some measure of respect--just not the respect that is given to a fully-formed human. (42) Supporters of the intermediary approach believe it could be considered immoral not to use embryos that would otherwise be destroyed to develop potential cures for diseases that affect millions of people. (43) IVF clinics in the U.S. routinely create more human embryos than are needed over the course of a fertility treatment and are therefore left with excess embryos that are subject to disposal. (44) This leads to the question of whether it is morally permissible to use/destroy such embryos for potentially lifesaving biomedical research. (45) While proponents of hESC research argue that it is ethically acceptable to use embryos for potentially life-saving biomedical research, opponents object and state that such research ultimately promotes and justifies the destruction of embryos. Additionally, even those that only ascribe the human embryo the fight to some form of intermediate respect...