Human embryonic stem cells (hES) and induced pluripotent stem cells (iPS) are pluripotent: they can become any type of cell in the body. While hES cells are isolated from an embryo, iPS cells can be made from adult cells. Somatic cells can be reprogrammed into pluripotent stem cells (45,46), called induced pluripotential stem cells (iPS cells). These iPS cell lines will have DNA that matches that of somatic cell donors and will be useful as disease models and possibly for allogeneic transplants. Some recognize that human embryos do not have the qualities essential to a right to life, but consider that they possess an intrinsic value that requires a certain degree of respect and imposes at least some moral limits on their use: “The life of a single human organism requires respect and protection. It does not matter in what form or in what form, because of the complex creative investment it represents, and because of our amazement at the divine or evolutionary processes that produce new life from the old. (Dworkin l992, 84). However, there are different views on the respect embryos enjoy and the limits of their use. Some opponents of HESC research believe that treating human embryos as mere research tools still shows no proper respect for them. Other opponents have a less absolutist view. For example, some consider embryos to be less valuable than more mature humans, but argue that the benefits of HESC research are too speculative to justify destroying embryos, and that the benefits could be obtained anyway by using undisputed stem cell sources (e.g., adult stem cells) (Holm 2003). One of the problems is that some research on gametes derived from stem cells requires the creation of embryos, whether using ES cells or iPS cells. In order to determine that a particular technique for obtaining human gametes from stem cells produces functional sperm and oocytes, it must be demonstrated that the cells can produce an embryo.
This involves the creation of embryos through in vitro fertilization. Since it would not be safe to implant embryos created in the early stages of research, the likely disposition of the embryos is that they would be destroyed. In such cases, the research would include all moral issues related to the creation and destruction of embryos for research. However, the creation of embryos for research in this situation would not require the destruction of embryos, as is the case for the creation of embryos to obtain stem cell lines. In principle, they could be stored indefinitely instead of destroyed. This would always expose the objection that life is created for instrumental purposes. But the power of the objection is questionable, as it is not clear that this instrumental use is more offensive than the routine and widely accepted practice of creating surplus IVF embryos in a reproductive context to increase the likelihood of producing a sufficient number of viable embryos to produce a pregnancy. Adult stem cells and umbilical cord blood stem cells do not raise particular ethical concerns and are widely used in research and clinical care. However, these cells cannot be multiplied in vitro and have not been definitively shown to be pluripotent.
Human stem cell research raises ethical issues that go beyond the role of institutional review boards (IRBs) in protecting human subjects, as well as the expertise of IRB members. There should be a strong scientific rationale for using human eggs and embryos to obtain new human stem cell lines. However, IRBs generally do not conduct a thorough scientific review. Some ethical issues in hESC research are not relevant to the protection of human subjects, for example, the concern that transplantation of human stem cells into non-human animals may lead to traits considered uniquely human. Since a human embryo cannot be reasonable at all, to claim that it has a rational nature is to assert that it has the potential to become an individual capable of discussion (Sagan & Singer 2007). But that an entity logically has this potential does not mean that it has the same status as beings who have realized part or all of the potential (Feinberg 1986). Moreover, with the advent of cloning technologies, the number of entities that we can now identify as potential individuals undoubtedly creates problems for those who attach great moral weight to the potential of the embryo. A single somatic cell, or HESC, can in principle (but not yet in practice) develop into a mature human under the right conditions – that is, the nucleus is transferred to an enucleated egg, the new egg is electrically stimulated to form an embryo, and the embryo is transferred into a woman`s uterus and given birth. If the basis of embryo protection is that they have the potential to become rational beings, then, according to some, we have reason to attribute high moral status to the trillions of cells that share this potential and to help as many of these cells as possible realize their potential (Sagan & Singer 2007, Savulescu 1999). Since this is an attitude we can expect almost everyone to oppose, it is not clear whether opponents of HESC research can actually base their position on the potential of the human embryo.
I would now like to turn to the legal memorandum prepared by the General Counsel of the Department of Health and Human Services (“HHS Note”). In its efforts to find that federal funding for embryonic stem cell research is consistent with congressional intent, HHS has overlooked some obvious facts and created its own arbitrary definition of a human embryo that has no basis in biology or federal law. Embryonic stem cells offer hope for new therapies, but their use in research has been hotly debated. Different countries have chosen to regulate embryonic stem cell research in very different ways. Mention embryonic stem cells in the pub and the issue always divides opinions. But what exactly are the ethical arguments and why are they so difficult to solve? It is surprising that despite the vast public debate – in Congress, during the 2004 and 2006 election campaigns, and on Sunday morning talk shows – relatively little attention has been paid to the moral question at the heart of the controversy: are opponents of stem cell research right in claiming that the unimplanted human embryo is already a human being? Morally equivalent to a person? So, is it a legal term? No, because the term “human” is not used in this part of the federal act. Instead, federal regulations since 1975 have defined the human embryo from implantation in the womb as a “human subject” who must be protected from harmful experiments, whether or not it is expected to survive to live birth.7 The current Fetal Research Act specifically requires that an aborted fetus be afforded the same protection as a fetus intended for live birth (42 U.S.C.289g(b)).