The ethical concerns about attempts to use NT to create children are well known. They include risks to the mother and the fetus that have been described in numerous reports by other advisory bodies and institutions (NBAC, 1997; NRC, 2002; President’s Council on Bioethics, 2002). As discussed in Chapter 1, this is a matter on which the U.S. National Academies and the scientific community worldwide have spoken with virtually a single voice. Attempts to create a child by means of NT are ethically objectionable at this time because, on the basis of experience with other mammalian species, producing one child might require hundreds of pregnancies and many abnormal late-term fetuses could be produced. Furthermore, some authorities believe that there can never be a fully normal product of NT because of the differences in imprinting between the genes in a transplanted somatic nucleus and those in the oocyte nucleus that it has replaced (Jaenisch, 2004), as well as a failure of epigenetic reprogramming in general. Such concerns led to Food and Drug Administration efforts to prohibit NT for reproductive purposes.1
Even in the absence of moral justification for attempting NT for reproductive purposes, some groups have announced their intention to pursue that objective, even if merely to generate publicity. An oversight system for hES cell research that might include NT as a source of cell lines will reinforce the ethical and scientific consensus that NT for reproductive purposes has no place in legitimate research. The danger that the efforts will continue is far greater in the absence of systematic oversight with its attendant accountability and transparency.
As a starting point for its deliberations, the Committee on Guidelines for Human Embryonic Stem Cell Research examined numerous other guidelines and regulations in use now or in the past to identify best practices and common features. Surveys of guidelines and regulations for embryo and/or hES cell research by this committee and others (Walters, 2004) revealed that common features of most, if not all, programs throughout the world include
A prohibition on nuclear transfer for reproductive purposes.
A prohibition on the culture of human embryos beyond 14 days after fertilization or when the primitive streak has appeared, whichever occurs first.
Most existing regulations and guidelines embody broad guiding principles. For example, most require that hES cell research projects aim to advance scientific and medical knowledge to benefit human health. Alternative methods (such as the use of existing hES cell lines or adult stem cells) must have been examined and shown to be
See FDA letter to investigators and sponsors at http://www.fda.gov/cber/ltr/aaclone.pdf.