Embryonic stem cell research and respect for human life: philosophical and legal reflections.

• Author: McCartney, James J.

1. INTRODUCTION

   Less than twenty-five years ago, bioethics was considered a somewhat arcane discipline. In 1978, the late Paul Ramsey, a noted Protestant ethicist, published a book entitled Ethics at the Edges of Life: Medical and Legal Intersections. (1) In this book, Ramsey considered abortion, euthanasia, defective infants, neonatal infanticide, and the refusal of life-prolonging technology. (2) Although the book was well received in some specialized academic circles, it did not have much impact on the media or on the popular culture of that time. One possible reason for this is that many people would just as soon avoid discussing issues that concern life and death. (3)

   Twenty-two years have passed since the publication of Ramsey's book, and many of the issues that were discussed still linger, yet these issues do not generally make headlines nor does the media cover them extensively. In this new millennium, we think of "the edges of life" in terms of issues like cloning and stem cell research, genetic therapy and counseling, reproductive technologies, organ and tissue transplantation, heart-lung machines, and artificial hearts. These are the issues that have come to the forefront because of the incredible and almost unimaginable advances in biology, chemistry, physics, and electronics during the past quarter century. These advances have already provided remarkable enhancements for human life and have the potential for even more improvements. This accelerated pace of scientific advancement has hindered the ability of our cultural values and laws to deal adequately with the opportunities and dangers such developments present. When it comes to the most recent scientific advancements dealing with the "edges of life," the media and the scientific and academic communities look to experts in bioethics for analysis, criticism, and support. The media and people in general are interested in these issues because while the creation of human life and the destruction of human embryos are often facts of this research, usually the focus is on the possible benefits to humans if the research can be developed into a new more therapeutic technology.

   Currently, one does not have to search far to discover major news outlets focusing on many of these "edges of life" issues, especially cloning and stem cell research. (4) On November 26, 2001, The New York Times published a story entitled Company Says It Produced Embryo Clones, (5) and on December 3, 2001, the Times ran a story entitled German Panel Recommends Imports of Stem Cells. (6) These latter two stories are based on the claim by Advanced Cell Technology (7) that it has cloned human embryos and intends to use these embryos as a source for producing stem cells, but not to create new individuals. (8) If these claims are accurate, and its research is successful, a company like Advanced Cell Technology might serve as a source of stem cells for the entire world. The stem cell controversy is so timely that on December 18, 2001, The New York Times devoted its entire Science Times section to a discussion of these issues. (9)

   In this article, I intend to focus on embryonic stem cell research, and on cloning and parthenogenesis insofar as these procedures are used in the creation of embryonic stem cells, and how these areas of research relate to ideas concerning respect for human life and dignity, and its treatment in American jurisprudence. First, I will briefly describe what stem cells are and how they are related to cloning. Then, after analyzing notions of respect for human life and their entailments, I will contemplate what level of respect is due to human embryos at the blastocyst stage, whether produced by fertilization of an egg by sperm, by cloning, or by parthenogenesis. From this ethical perspective, I will then consider three related but distinct questions: (1) What are the ethical issues involved in research using stem cells derived from adult persons or from cells saved from the umbilical cord? (2) What are the ethical issues involved in research using stem cells derived from frozen embryos? (3) What are the ethical issues involved in creating embryos by cloning, parthenogenesis, or in-vitro fertilization solely for the purpose of deriving embryonic stem cells to be used in research?

   Finally, I will review relevant legal material focusing on the federal regulations relating to embryonic stem cell research, President Bush's recent administrative decision to restrict future federal funding to those embryonic stem cell lines already established and developed through private funding, and the current debate in Congress over stem cell research. I will conclude by advocating additional federal support for research involving new stem cell lines that may be developed from embryos that were originally frozen for the purpose of in-vitro fertilization but are now no longer needed, and thus, scheduled for destruction.

2. STEM CELLS AND CLONING

   Stem cells can briefly be described as unspecialized cells that give rise to various types of specialized cells. In more scientific terms, stem cells are described as pluripotent cells, which mean that they have the ability to develop into many kinds of tissues and organs of the body. (10) These pluripotent cells have the capacity for prolonged self-renewal, and can be induced by chemical and electric means to form different types of specialized somatic cells and tissues. Stem cells are retrieved from the body by simple removal or extraction. (11) When stem cells are derived from the umbilical cord, which is saved after birth and then frozen, they can eventually produce bone marrow. (12) "[Adult] stem cells--found ... in various locations in the adult body--can form a number of different tissues and so could in theory[,] be used to treat a vast array of diseases." (13) Embryonic stem cells, on the other hand, are derived from embryos in the following way: "At the point at which dividing cells develop into a hollow ball, the embryo is called a blastocyst. [Human embryonic stem] cells are derived by destroying the outer shell of the blastocyst, which would normally become the placenta, and culturing cells from the inner cell mass." (14) These cells, which are grown in tissue culture and can actually develop into organs, are now referred to as pluripotent rather than totipotent since they are no longer able to develop into embryos. (15)

   A cloned organism is defined more technically as an individual grown from a single somatic cell nucleus of its parent that has been implanted into an egg cell from which the nucleus has been removed. (16) Then, the enucleated egg cell containing the implanted nucleus is stimulated electrically. Here, cell division and the production of a new embryo begin to take place. Cloning was pushed to the forefront of debate a few years ago by the production of Dolly the sheep. (17) In Dolly's case, a cell nucleus from her mother's udder was used to create her. (18) Somatic cells are any of the cells of the body except sperm cells and egg cells, e.g., the udder cell whose nucleus was used to produce Dolly. (19) The clone is genetically identical to the parent whose cell nucleus was used, since both share the same genotype--identical nuclear DNA. (20) Parthenogenesis is the stimulation of an immature egg cell, which is still attached to a polar body that contains the other half of its DNA, in order to induce cell division and the eventual production of stem cells. (21)

   For background purposes, two other phenomena should be mentioned at this point: twinning and chimera formation. Up until the formation of the primitive streak, which will develop into the spinal cord, and cell differentiation, which occurs about fourteen days after fertilization, the developing embryo can cleave naturally or artificially, resulting in the production of identical siblings. (22) Therefore, embryonic cells that are still part of the inner cell mass are described as totipotent because they can give rise to new organisms, i.e., twins. (23) Another possibility during this stage is that two developing embryonic cell masses with different genotypes will fuse to form what is called a chimera. (24) "A chimera is an organism whose cells derive from two or more distinct zygote lineages." (25) After the cells have begun to differentiate and the primitive streak has formed, twinning and chimera formation are no longer possible. (26)

3. RESPECT FOR HUMAN LIFE

   Respect for human life is the leitmotif of the Universal Declaration of Human Rights approved by the General Assembly of the United Nations in 1948. (27) This document states, in part, that "[a]ll human beings are born free and equal in dignity and rights," (28) that "[e]veryone is entitled to all the rights and freedoms set forth in this Declaration, without distinction of any kind, such as race, colour, sex, language, religion, political or other opinion, national or social origin, property, birth or other status," (29) and that "[e]veryone has the right to life, liberty and security of person." (30) Although the Declaration never asserts a Divine origin for these rights, it does maintain that they are "equal and inalienable rights of all members of the human family." (31) This means imply that no human being should be denied these rights.

   Many assert that this respect for human life is due only to persons, but if we examine the literature we discover that there are many different and conflicting notions as to what exactly constitutes "personhood." This is not surprising in an age that eschews metaphysics and asserts that much of our understanding of reality is invented, created, or is the product of interpretation. A more robust respect for human life would emerge if we acknowledged that all individuals possess certain inalienable rights, and that organisms developing toward human individuation should be accorded some measure of respect and dignity--considering that they are destined to...