Bioethics and Cloning, Part 1
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Bioethics Research Library The Joseph and Rose Kennedy Institute of Ethics Box 571212, Georgetown University Washington, DC 20057-1212 202-687-3885; fax: 202-687-8089 [email protected] http://bioethics.georgetown.edu Bioethics and Cloning, S Part 1 Susan Cartier Poland C Laura Jane Bishop September, 2002 O This is Part 1 of a two-part Scope Note on Bioethics and Cloning. The two parts were published consecutively in the September and December 2002 issues of the P Kennedy Institute of Ethics Journal. Introduction “Clone” is a collective noun (I, Stewart 1997, p. 771). A collective noun names E a group and is composed of individual members, such as “herd” or “flock.” Derived from the Greek klôn for twig or slip, “clone” was first used in biology to describe the aggregate of asexually produced progeny of an individual, either naturally occurring or man-made; the definition later expanded to mean a group of genetically identical members who originate from a single ancestor. Thus, a N clone is a group that results from the process of asexual reproduction. In nature, cloning occurs either by parthenogenesis (reproduction without O fertilization) or by fission (embryo splitting). In a pioneering experiment in 1952, Robert Briggs and Thomas J. King (I, 1952), cancer researchers at the Institute for Cancer Research (today part of the Fox Chase Cancer Center) in Philadelphia, demonstrated on frogs another method of cloning by transplanting nuclei into T enucleated cells, a technique called “nuclear transplantation,” which John B. E Gurdon and colleagues (I, 1958, 1975) used to create clones of frogs. 41 1 Then, in the late 1970s and early 1980s, two back- to-back frauds in cloning occurred. First, the TABLE OF CONTENTS cloning of a human described by American science journalist David Rorvik in the 1978 book Introduction. 1 In His Image was called a hoax by a court in I. History of the Science.. 4 1982. Second, the cloning of three mice, II. Historical Commentary. 7 announced by German wunderkind Karl Illmensee III. Animal Welfare. 9 (I) to scientific circles in 1979 (and to the public IV. Laws and Legal Literature.. 11 in 1981), could not be proven to be true, A. United States. 11 according to convincing evidence by McGrath and B. International. 12 Solter (I) published in 1984. C. Other.. 14 D. Legal Literature. 14 With their pronouncement that mammalian cloning was impossible, McGrath and Solter essentially stopped cloning research and funding theology and philosophy. It fosters questions for such biological research. So by the mid-1980s, about the meaning and purpose of life, the limits instead of further investigating cloning, of human powers to intervene in research and developmental biologists studied embryology therapy, and what it means to be human and related to in vitro fertilization, while molecular animal. In addition, environmentalists and organic biologists studied recombinant DNA under the farmers raise concerns about the effect of novel newly relaxed NIH guidelines. These two strands animals and plants on the environment, while of scientific investigation came together in the nutritionists and the lay public wonder about the work of Ian Wilmut, (I) who created in vitro health implications of cloning and consuming embryos using nuclear transplantation to mass quantities of bioengineered plants. reproduce genetically engineered cattle. Wilmut was seeking a way to increase the successful birth Keeping in mind at least four distinctions may rate when, in the 1990s, he produced identical help in understanding media reports of scientific twin sheep, Megan and Morag, cloned from an developments in cloning technology, in evaluating embryonic cell, followed by another sheep, Dolly, claims about the promise of cloning technologies, cloned from an adult cell. The birth of a mammal and in being clear about ethical and theological from an embryo whose genetic material came arguments for and against cloning. First, one must from an adult cell firmly re-established the distinguish the purpose of the cloning: Is it being possibility of cloning from adults. Prior to Dolly’s done purely for research or for research to birth, scientists believed that adult cells lost the understand and develop treatments or cures for ability to dedifferentiate—i.e., to become diseases or disorders (optimistically called unspecialized—and so could not direct the therapeutic cloning) or for reproductive purposes? development of an embryo through to birth. An often discussed focus of “therapeutic cloning” is the creation of cells, tissues, or fully formed The 1997 announcement of Dolly’s birth initiated organs for transplantation into humans to the present widespread discussion of cloning. regenerate or replace damaged, diseased, Because of its potentially vast applications across deformed, or worn-out parts. These resources, human health, medicine, agriculture, and cloned from a person’s own cells, would have a business/economics, cloning raises a host of common genetic identity, helping to avoid issues including those concerning: genetics and rejection based on genetic incompatibility. In genetic engineering, patenting, animal rights addition, such cloned cells, tissues, or organs and/or animal welfare (especially for transgenic, would help to alleviate the present shortage of research, or cloned animals), organ organs and tissues available for transplant. The transplantation, reproduction, eugenics, goal of reproductive cloning would be to produce pharmacology (drug production using transgenic an entire organism—animal or human. The animals), research practices, informed consent, genetic makeup of such “offspring” would be stem cell research, women’s rights, children’s virtually identical to that of the individual from rights, parental rights and responsibilities, and whom the genetic material is obtained. Questions 2 might also arise about the purpose for which the whether more than one species is involved also cloned individual was produced—e.g., to replace must be discerned. For example, the cells to be a dead or dying individual; to serve as an organ, cloned can be embryonic or fetal or adult. They tissue, or blood resource for its already existing can be germ cells or somatic (body) cells. The genetic progenitor; or simply to create offspring. source of the somatic cells can vary—mammary tissue (as with Dolly) or cumulus cells, which Second, one should distinguish among multiple surround and nurture the oocyte during maturation cloning techniques: Does the cloning occur by of the egg in the female ovary (as with CC, a parthenogenesis (oocyte division without cloned cat) or skin cells, and so forth. Cloning fertilization), blastomere separation (embryo efforts may combine genetic material from a splitting or twinning), or somatic cell nuclear single species or from different species—the latter transfer (SCNT), in which the nucleus of a process results in a transgenic animal. somatic cell, from an adult, is transferred into an already enucleated egg? In addition, which of the Ethical Issues in Animal Cloning different procedures available is used to combine the nucleus with the enucleated egg The cloning of animals as part of an emergent (ooplasm)—e.g., microsurgical injection or technology for reproducing farm, companion, and electrofusion? In all cases, although the host egg research animals often is taken for granted. contributes its mitochondrial DNA (about 2 Despite this acceptance, animal cloning raises percent of the total DNA), the vast majority of the concerns about the pain and suffering that may be genetic material of the developing embryo comes caused them by purposely tinkering with their from the transplanted nucleus. It is possible that genetic makeup and the way in which they are the technique itself may influence the success and conceived. Potential physical concerns are low post-birth health of offspring. success rates, problems with gestation and delivery, concerns about fetal anomalies, and Third, cloning must be distinguished from stem worries over increased vulnerability of clones to cell research. The same technique, SCNT, may be aging, disease, or disability. Deeper philosophical used to create embryos either for the purpose of issues require consideration, such as the developing in vitro stem cell lines or for the acceptability and implications of altering the purpose of in vivo gestation. SCNT is, however, genetic makeup of animals, especially in a world only one method of producing stem cells. Stem dominated by humans, as do practical concerns cells also can be obtained from surplus embryos that efforts to create “ideal” animals will diminish from IVF treatments for infertility, from embryos genetic diversity (with implications for hardiness created by IVF specifically for research purposes, and disease resistance), more rapidly, than will the from embryonic germ cells from aborted fetuses, selective breeding practices already in use. from umbilical cord blood, and from some adult Concern encompasses not only the animals born tissues—e.g., bone marrow or skin or blood—that of the cloning procedure, but also the animals have been reprogrammed to be totipotent without whose oocytes and genetic material are used, the use of the nuclear transfer technique (Danish those who serve as in vivo incubators, and those Council of Ethics, Cloning: Statements from the who gestate the embryos. Animals providing the Danish Council of Ethics, Copenhagen: The eggs into which the DNA will be transplanted Council, 2002, Part 2, I).