Radiographic assessment of the skeletons of Dolly and other clones finds no abnormal osteoarthritis.

Our recent report detailing the health status of cloned sheep concluded that the animals had aged normally. This is in stark contrast to reports on Dolly (first animal cloned from adult cells) whose diagnoses of osteoarthritis (OA) at 5½ years of age led to considerable scientific concern and media debate over the possibility of early-onset age-related diseases in cloned animals. Our study included four 8-year old ewes derived from the cell line that gave rise to Dolly, yet none of our aged sheep showed clinical signs of OA, and they had radiographic evidence of only mild or, in one case, moderate OA. Given that the only formal record of OA in Dolly is a brief mention of a single joint in a conference abstract, this led us to question whether the original concerns about Dolly's OA were justified. As none of the original clinical or radiographic records were preserved, we undertook radiographic examination of the skeletons of Dolly and her contemporary clones. We report a prevalence and distribution of radiographic-OA similar to that observed in naturally conceived sheep, and our healthy aged cloned sheep. We conclude that the original concerns that cloning had caused early-onset OA in Dolly were unfounded.

Ethical issues regarding human cloning: a nursing perspective.

Advances in cloning technology and successful cloning experiments in animals raised concerns about the possibility of human cloning in recent years. Despite many objections, this is not only a possibility but also a reality. Human cloning is a scientific revolution. However, it also introduces the potential for physical and psychosocial harm to human beings. From this point of view, it raises profound ethical, social and health related concerns. Human cloning would have an impact on the practice of nursing because it could result in the creation of new physiological and psychosocial conditions that would require nursing care. The nursing profession must therefore evaluate the ethics of human cloning, in particular the potential role of nurses. This article reviews the ethical considerations of reproductive human cloning, discusses the main reasons for concern, and reflects a nursing perspective regarding this issue.

Cloning of Homo sapiens? No!

Animal cloning by nuclear transplantation was first developed in the northern leopard frog, Rana pipiens. It was soon extended to other amphibian species and within time, to various mammalian species. The production of a cloned sheep (Dolly) from an adult nuclear donor reawakened interest in human cloning. Nuclear transfer for the production of animal clones has served experimental biology well. Nonetheless, the potential burden of developmental hazards, scientists and funds diverted from more needy causes, as well as the potential assault on the concept of family has led the author to oppose human cloning.

Biotechnology in reproductive medicine.

In this review I am summarizing the past and current progress in the field of pharmaceutical, diagnostic, therapeutic, and reproductive cloning in mammals. Several human gene products can be pharmaceutically explored in transgenic farm animals and employed for medical applications. Preimplantation genetic diagnosis (PGD) is utilizing modern molecular cloning techniques to detect genetic and chromosomal aberrations in early embryos originating from patients with inborn errors at risk for hereditary diseases or age-related risk for abnormal karyotype. Stem cell engineering from early human embryos is creating new and promising but also controversial applications for therapeutic and regenerative medicine. Potential risk factors for reproductive cloning are presented and discussed in the context of possible developmental malformations, frequently observed after embryo culture and cloning in farm animals. Future extension of biotechnology to human reproductive cloning is currently under worldwide dispute.

Animal cloning. Clones: a hard act to follow.

Often left out of news reports of cloned animals is the fact that for every 100 attempts, just two or three live offspring typically result. Now many researchers are going back to the lab to attempt to find out why. They are probing fundamental questions of cell biology, as well as trying to figure out whether there is something inherently flawed in "asexual" reproduction in mammals, or whether some problem lies in the in vitro component of the process. For now, the serious obstacles suggest that human cloning may be a long way off.

Genetic technologies and achieving health for populations.

The remarkable progress in genetics over the last 50 years has led to the development of genetic technologies to identify or alter genes in living organisms, and these technologies can be applied to people. This article presents background information on the role of genetics in human disease, outlines the technologies, and discusses the sources of the strong push for a genetic approach to ill-health and some implications and harmful consequences of using these genetic technologies. The determinants of most diseases are complex and are embedded in a social context. To focus on only one strand of this web--the genetic strand--because it is one that may be amenable to biological/pharmaceutical treatment, although profitable for industry, does not address other important determinants of health and may lead to a harmful overemphasis on genetic approaches. The author outlines some limitations to the potential contribution of genetic technologies to population health across the globe and the need for policy development if these technologies are to have an appropriate place in health care.