Patient-specific embryonic stem cells derived from human SCNT blastocysts

[The amazing story of the fraudulent cloned embryos and what it tells us about science, technology, and the media]

Based on news reports from Brazilian papers, the article examines the case of scientific fraud involving cloned embryos, committed by South Korean scientist Hwang. The media generally focus on the intellectual process of science, its discoveries, and the new possibilities it promises. In this case, however, science is shown the other way around, revealing a web that interweaves elements of a radically disparate nature, like the Korean government, researchers, tools, research funds, human eggs and funguses, scientific journals, among others. These ties are what make up science in practice, yet they only become visible in the media when there is tension between them and, in this case, when something illicit happens.

Sex and reproduction: an evolving relationship

BACKGROUND

Although sexual activity has, until very recently, been essential to reproduction, this did not preclude the non-reproductive importance of sexual relationships and non-conceptive copulations. Technological advances, however, now allow for both sex without reproduction and reproduction without sex. This review summarizes social and ethical commentaries on the new relationship between sex and reproduction.

METHODS

For each main area discussed, a systematic search was made using (depending on the subject) PubMed, Medline, ScienceDirect, classic books, Google and/or religious websites. The search focused on publications between 1975 and 2009, although some materials from the first part of the 20th century were also utilized.

RESULTS

The classic picture of sex for reproduction and bonding between mating partners is increasingly being replaced by reproduction separate from sexual activity. Although not every advance in assisted reproduction produced, per se, a further separation from sexual intercourse, these two fundamental human activities are today increasingly carried out independently, as reproduction is possible, not only without sex, but even through the intervention of more than two partners. The possibility of reproduction with only one or even no gametes, although highly controversial and not yet feasible, is nonetheless being investigated.

CONCLUSIONS

Technological advances in the field of reproductive biology have enabled couples considered infertile to conceive and have healthy babies, causing a revolution in culture and customs. Today the independence of sex and reproduction is established and in the future human reproduction may move even further away from the sexual act, an option definitely unacceptable to some ethicists.

The legacy of the Hwang case: research misconduct in biosciences

This paper focuses on the infamous case of Hwang Woo Suk, the South-Korean national hero and once celebrated pioneer of stem cell research. After briefly discussing the evolution of his publication and research scandal in Science, I will attempt to outline the main reactions that emerged within scientific and bioethical discourses on the problem of research misconduct in contemporary biosciences. What were the ethical lapses in his research? What kind of research misconduct has been identified? How this kind of misconduct affects scientific integrity? How to avoid it? Focusing on these questions, the paper interprets the Hwang's case as a case study that might shed light on the worst aspects of highstakes global science. This case presents a group of problems that might endanger scientific integrity and public trust. Regulatory oversight, ethical requirements and institutional safeguards are often viewed by the scientific community as merely decelerating scientific progress and causing delays in the application of treatments. The Hwang's case represents how unimpeded progress works in contemporary science. Thus, the case might shed light on the often neglected benefits of "the social control of science".

Cell-based therapies for Parkinson's disease: past, present, and future

Parkinson's disease (PD) researchers have pioneered the use of cell-based therapies (CBTs) in the central nervous system. CBTs for PD were originally envisioned as a way to replace the dopaminergic nigral neurons lost with the disease. Several sources of catecholaminergic cells, including autografts of adrenal medulla and allografts or xenografts of mesencephalic fetal tissue, were successfully assessed in animal models, but their clinical translation has yielded poor results and much controversy. Recent breakthroughs on cell biology are helping to develop novel cell lines that could be used for regenerative medicine. Their future successful clinical application depends on identifying and solving the problems encountered in previous CBTs trials. In this review, we critically analyze past CBTs' clinical translation, the impact of the host in graft survival, and the role of preclinical studies and emerging new cell lines. We propose that the prediction of clinical results from preclinical studies requires experimental designs that allow blind data acquisition and statistical analysis, assessment of the therapy in models that parallel clinical conditions, looking for sources of complications or side effects, and limiting optimism bias when reporting outcomes.

Oversight framework over oocyte procurement for somatic cell nuclear transfer: comparative analysis of the Hwang Woo Suk case under South Korean bioethics law and U.S. guidelines for human embryonic stem cell research

We examine whether the current regulatory regime instituted in South Korea and the United States would have prevented Hwang's potential transgressions in oocyte procurement for somatic cell nuclear transfer, we compare the general aspects and oversight framework of the Bioethics and Biosafety Act in South Korea and the US National Academies' Guidelines for Human Embryonic Stem Cell Research, and apply the relevant provisions and recommendations to each transgression. We conclude that the Act would institute centralized oversight under governmental auspices while the Guidelines recommend politically-independent, decentralized oversight bodies including a special review body for human embryonic stem cell research at an institutional level and that the Guidelines would have provided more vigorous protection for the women who had undergone oocyte procurement for Hwang's research than the Act. We also suggest additional regulations to protect those who provide oocytes for research in South Korea.

Human parthenogenetic embryonic stem cells: one potential resource for cell therapy

Pluripotent stem cells derived from somatic cells through such processes as nuclear transfer or induced pluripotent stem (iPS) cells present an important model for biomedical research and provide potential resources for cell replacement therapies. However, the overall efficiency of the conversional nuclear transfer is very low and the safety issue remains a major concern for iPS cells. Embryonic stem cells (ESCs) generated from parthenogenetic embryos are one attractive alternative as a source of histocompatible cells and tissues for cell therapy. Recent studies on human parthenogenetic embryonic stem cells (hPG ESCs) have revealed that these ESCs are very similar to the hESCs derived from IVF or in vivo produced blastocysts in gene expression and other characteristics, but full differentiation and development potential of these hPG ESCs have to be further investigated before clinical research and therapeutic interventions. To generate various pluripotent stem cells, diverse reprogramming techniques and approaches will be developed and integrated. This may help elucidate the fundamental mechanisms underlying reprogramming and stem cell biology, and ultimately benefit cell therapy and regenerative medicine.

POSSIBLE THERAPY OF MALE INFERTILITY BY REPRODUCTIVE CLONING: ONE CLONED HUMAN 4-CELL EMBRYO

This study was conducted to evaluate the preimplantation embryonic potential of adult somatic cells from an infertile man using an interspecies bioassay for quality control and also to create human embryos via somatic cell nuclear transfer (SCNT). Skin tissue was biopsied from infertile man to obtain fibroblast cells. These cells were fused with both enucleated bovine oocytes obtained commercially and human oocytes obtained from his wife. SCNT-reconstructed oocytes were cultured in-vitro. Interspecies SCNT embryos were prepared for PCR and DNA analysis. From 13 SCNT-reconstructed bovine oocytes, 7 embryos developed (54%). DNA sequencing of these interspecies embryos showed the presence of human genomic DNA specific for the fibroblast cells of the man. From three SCNT-reconstructed human oocytes, one developed to the 4-cell stage and was subsequently transferred into the patient's uterus. Blood ss-hCG levels showed a negative pregnancy result. Human fibroblast cells from an infertile patient can promote embryonic development in interspecies SCNT. This is the first evidence of the creation and transfer of a human cloned embryo for reproductive purposes. Even though no pregnancy was established, human reproduction via SCNT may be possible and applicable in the future for patients with severe male or female infertility that have no other alternative options for procreating their own offspring.

The immune boundaries for stem cell based therapies: problems and prospective solutions

Stem cells have fascinated the scientific and clinical communities for over a century. Despite the controversy that surrounds this field, it is clear that stem cells have the potential to revolutionize medicine. However, a number of significant hurdles still stand in the way of the realization of this potential. Chiefly among these are safety concerns, differentiation efficiency and overcoming immune rejection. Here we review current progress made in this field to optimize the safe use of stem cells with particular emphasis on prospective interventions to deal with challenges generated by immune rejection.

Hematopoiesis from Human Embryonic Stem Cells: Overcoming the Immune Barrier in Stem Cell Therapies

The multipotency and proliferative capacity of human embryonic stem cells (hESCs) make them a promising source of stem cells for transplant therapies and of vital importance given the shortage in organ donation. Recent studies suggest some immune privilege associated with hESC-derived tissues. However, the adaptability of the immune system makes it unlikely that fully differentiated tissues will permanently evade immune rejection. One promising solution is to induce a state of immune tolerance to a hESC line using tolerogenic hematopoietic cells derived from it. This could provide acceptance of other differentiated tissues from the same line. However, this approach will require efficient multilineage hematopoiesis from hESCs. This review proposes that more efficient differentiation of hESCs to the tolerogenic cell types required is most likely to occur through applying knowledge gained of the ontogeny of complex regulatory signals used by the embryo for definitive hematopoietic development in vivo. Stepwise formation of mesoderm, induction of definitive hematopoietic stem cells, and the application of factors key to their self-renewal may improve in vitro production both quantitatively and qualitatively.

For love or money? The saga of Korean women who provided eggs for embryonic stem cell research

In 2004 and 2005, Woo-Suk Hwang achieved international stardom with publications in Science reporting on successful research involving the creation of stem cells from cloned human embryos. The wonder and success all began to unravel, however, when serious ethical concerns were raised about the source of the eggs for this research. When the egg scandal had completely unfolded, it turned out that many of the women who provided eggs for stem cell research had not provided valid consents and that nearly 75% of the women egg providers had received cash or in-kind payments. Among those who did not receive direct benefits, some cited patriotism as their reason for participating in embryonic stem cell research, hence the question "for love or money?"--namely, patriotism versus payment. This paper summarizes the Hwang debacle with particular attention to the egg scandal and ends with some preliminary thoughts on patriotism as a motive for research participation.

"You are our only hope": trading metaphorical "magic bullets" for stem cell "superheroes"

In the wake of two recent developments in stem cell research, it is a fitting time to reassess the claim that stem cells will radically transform the concept and function of medicine. The first is the U.S. Food and Drug Administration's decision in January 2009 to approve Geron Corporation's Phase I clinical trial using human embryonic stem cells for patients with spinal cord injuries. The second is the National Institutes of Health's decision to permit federal funding of research using donated IVF human embryos in their July 2009 Guidelines on Human Stem Cell Research. We are now poised to see whether stem cell research can deliver on what it promises. However, what exactly does it promise and how? Moreover, who is doing the promising? Turning to the use of metaphor can help us to answer these questions and enable us to develop a better appreciation of the unique features of promised stem cell therapies. Indeed, metaphors have exerted profound influence in medicine, and it is fitting that we seek new metaphors for new therapies where appropriate. In this case, other metaphors such as magic bullets or the Holy Grail cannot capture what is unique about stem cells. Accordingly, I propose a new metaphor: the stem cell superhero. Stem cell superheroes are characterized by the following traits: they are seemingly capable of fighting the evil of virtually all disease (unlike "magic bullets") and they seem to be our only hope of doing so, although to summon them we must make difficult moral choices. In the course of assessing the merits of three recent yet covert references to the superhero metaphor, I conclude that this powerful new paradigm employs a problematic logic (i.e., we cannot know that something is "our only hope"), but that the aspiration as such is a good one.

Animal eggs for stem cell research: a path not worth taking

In January 2008, the Human Fertilisation and Embryology Authority (HFEA) (London, UK) issued two 1-year licenses for cytoplasmic hybrid embryo research. This article situates the HFEA's decision in its wider scientific and political context in which, until quite recently, the debate about human embryonic stem cell research has focused narrowly on the moral status of the developing human embryo. Next, ethical arguments against crossing species boundaries with humans are canvassed. Finally, a new argument about the risks of harm to women egg providers resulting from research involving the creation of humanesque cytoplasmic hybrid embryos is elaborated. Taken together these ethical concerns about the moral status of the human embryo, about the ethics of crossing species boundaries with humans, and about the potential harms to women (concerns that independently are more or less weighty for different constituencies), provide good reason to eschew humanesque cytoplasmic hybrid embryo research in favor of less ethically controversial means to the laudable end of successful regenerative medicine.

Stem cells in urology

The shortage of donors for organ transplantation has stimulated research on stem cells as a potential resource for cell-based therapy in all human tissues. Stem cells have been used for regenerative medicine applications in many organ systems, including the genitourinary system. The potential applications for stem cell therapy have, however, been restricted by the ethical issues associated with embryonic stem cell research. Instead, scientists have explored other cell sources, including progenitor and stem cells derived from adult tissues and stem cells derived from the amniotic fluid and placenta. In addition, novel techniques for generating stem cells in the laboratory are being developed. These techniques include somatic cell nuclear transfer, in which the nucleus of an adult somatic cell is placed into an oocyte, and reprogramming of adult cells to induce stem-cell-like behavior. Such techniques are now being used in tissue engineering applications, and some of the most successful experiments have been in the field of urology. Techniques to regenerate bladder tissue have reached the clinic, and exciting progress is being made in other areas, such as regeneration of the kidney and urethra. Cell therapy as a treatment for incontinence and infertility might soon become a reality. Physicians should be optimistic that regenerative medicine and tissue engineering will one day provide mainstream treatment options for urologic disorders.

Does government regulation inhibit embryonic stem cell research and can it be effective?

The UK was one of the first countries to introduce legislation regulating embryo research, and the British Parliament has taken a liberal view of the field. However, even in the UK, regulation of human embryonic stem cell (ESC) research has had drawbacks, and the regulatory framework is somewhat inconsistent and imposes considerable bureaucracy. There are around 33 countries that have broadly liberal legislation; each has a different view of what is permissible. Only about eight of these countries have contributed significantly to published research in the field. Paradoxically, in spite of tight federal restrictions, the USA remains the most productive country in terms of the number and quality of peer review research publications. But even in our increasingly global society, complex regulation will become progressively irrelevant and impossible to impose effectively because attitudes will continue to vary widely in different countries and because of international travel and trade. Consequently, there is a universal need for scientists to demonstrate their recognition of the ethical and commercial conflicts that may arise in their research and engage in public debate and dialogue to ensure responsible activity that benefits their research and reflects the values of society.

Strategies and new developments in the generation of patient-specific pluripotent stem cells

Generating pluripotent stem cells directly from cells obtained from patients is one of the ultimate goals in regenerative medicine. Two "reprogramming" strategies for the generation of pluripotent stem cells from somatic cells have been studied extensively: nuclear transfer to oocytes and fusion with ES cells. The recent demonstration that, in mouse, nuclear transfer into zygotes can also be effective if the recipient cells are arrested in mitosis provides an exciting new avenue for this type of approach. Patient-specific pluripotent cells could potentially also be generated by the spontaneous reprogramming of bone marrow cells, spermatogonial cells, and parthenogenetic embryos. A third overall type of strategy arose from the demonstration that pluripotent stem (iPS) cells can be generated from mouse fibroblasts by the introduction of four transcription factors (Oct-3/4, Sox2, c-Myc, and KLF4). Recent work has underlined the potential of this strategy by improving the efficiency of the process and demonstrating that iPS cells can contribute to many different tissues in vivo, including the germline. Taken together, these studies underscore the crucial roles of transcription factors and chromatin remodeling in nuclear reprogramming.

Sources of stem cells for regenerative medicine

The shortage of organ donors for regenerative medicine has stimulated research on stem cells as a potential resource for cell-based therapy. Stem cells have been used widely for regenerative medicine applications. The development of innovative methods to generate stem cells from different sources suggests that there may be new alternatives for cell-based therapies. Here, we provide an overview of human embryonic stem cells (hES) and the methods for obtaining these cells and other broadly multipotent or pluripotent cell types. These methods include somatic cell nuclear transfer, single cell embryo biopsy, arrested embryos, altered nuclear transfer, and reprogramming somatic cells. We also discuss the use of amniotic-fluid derived stem cells (AFS) for potential patient-specific therapies.

Pluripotency and nuclear reprogramming

Embryonic stem cells are promising donor cell sources for cell transplantation therapy, which may in the future be used to treat various diseases and injuries. However, as is the case for organ transplantation, immune rejection after transplantation is a potential problem with this type of therapy. Moreover, the use of human embryos presents serious ethical difficulties. These issues may be overcome if pluripotent stem cells are generated from patients' somatic cells. Here, we review the molecular mechanisms underlying pluripotency and the currently known methods of inducing pluripotency in somatic cells.

The road to pluripotence: the research response to the embryonic stem cell debate

The controversies surrounding embryonic stem cell research have prompted scientists to invent beyond restrictive national policy and moral concerns. The impetus behind these reports comes from different sources, including individually held moral beliefs, societal pressures and resource constraints, both biological and financial. Along with other contributions to public policy such as advocacy or public testimony, experimentation and scientific curiosity are perhaps more natural responses scientists use to surmount impediments to research. In a research context, we review the history of the first stem cell discoveries, and describe scientific efforts leading up to recent reports of pluripotent lines made without the use of human embryos and eggs. We argue that despite the promise of these new lines, we must not lose sight of fundamental questions remaining at the frontiers of embryology and early human development. The answers to these questions will impact studies of genetics, cell biology and diseases such as cancer, autoimmunity and disorders of development. Human embryonic stem cell research is barely a decade old. The recent pace of discovery--in spite of federal restrictions--is testament to the potential of these cells to uncover some of biology's most intractable mysteries.

Research progress and application prospect of induced pluripotent stem cells

Recent reports demonstrate that mouse somatic cells can be directly reprogrammed into pluripotent embryonic stem (ES) cell-like cells by in vitro introduction of four transcription factors, Oct4, Sox2, c-Myc and Klf4. These cells are designated as induced pluripotent stem (iPS) cells. Similarly, the transfection with these four transcription factors or a cocktail of Oct4, Sox2, Nanog and LIN28 has been shown to be sufficient to reprogram human somatic cells to iPS cells that are indistinguishable from human ES cells. Since reactivation of the c-Myc transgene has been reported to increase tumorigenicity in the chimeras and progeny mice, a modified protocol with only three factors (Oct4, Sox2 and Klf4) has been recently used to make mouse and human iPS cells from adult dermal fibroblasts. Based upon the data from recent publications, human iPS cell lines should be useful in the establishment of new disease models and in drug development, and might require further investigation about the feasibility in transplantation medicine.

Generation of embryonic stem cells: limitations of and alternatives to inner cell mass harvest

Embryonic stem (ES) cells are pluripotent cells derived from the inner cell mass of the early mammalian embryo. Because of their plasticity and potentially unlimited capacity for self-renewal, ES cells have generated tremendous interest both as models for developmental biology and as possible tools for regenerative medicine. This excitement has been attenuated, however, by scientific, political, and ethical considerations. In this article the authors describe somatic cell nuclear transfer and transcription-induced pluripotency, 2 techniques that have been used in attempts to circumvent the need to derive ES cells by the harvest of embryonic tissue.

Therapeutic potentials of human embryonic stem cells in Parkinson's disease

The loss of dopaminergic neurons of the substantia nigra is the pathological hallmark characteristic of Parkinson's disease (PD). The strategy of replacing these degenerating neurons with other cells that produce dopamine has been the main approach in the cell transplantation field for PD research. The isolation, differentiation, and long-term cultivation of human embryonic stem cells and the therapeutic research discovery made in relation to the beneficial properties of neurotrophic and neural growth factors has advanced the transplantation field beyond dopamine-producing cells. The present review addresses recent advances in human embryonic stem cell experimentation in relation to treating PD, as well as cell transplantation techniques in conjunction with alternative therapeutics.

Derive and conquer: sourcing and differentiating stem cells for therapeutic applications

Although great progress has been made in the isolation and culture of stem cells, the future of stem-cell-based therapies and their productive use in drug discovery and regenerative medicine depends on two key factors: finding reliable sources of multipotent and pluripotent cells and the ability to control their differentiation to generate desired derivatives. It is essential for clinical applications to establish reliable sources of pathogen-free human embryonic stem cells (ESCs) and develop suitable differentiation techniques. Here, we address some of the problems associated with the sourcing of human ESCs and discuss the current status of stem-cell differentiation technology.

General principles regarding the use of adult stem cells

With only a few, almost inevitable exceptions, biomedical research has developed within the last 50 years under the tutelage of ethical standards of notable precision. In the vast world of scientific investigation, few disciplines can boast of having realized documents of such ethical rigour, and respect for the integrity and intrinsic value of the human person has been one of the cardinal principles of the researcher. Research is intrinsic to the medical profession; the reward of research is knowledge and its techniques are ordered towards maintenance of human health. Since this end concerns human beings, it demands an extremely rigorous ethical approach. Ethical aspects are present from the first moments of the experimental project and occur on three levels: choice of the objectives, selection and use of the appropriate means for the study, and application of resultant new discoveries. Today, our moral attention cannot be reduced to a cost-benefit analysis. Biomedical sciences and medicine have overlapping areas of interest that can be sources of tension: the good of the subject versus scientific utility; profit versus complexity of research; liberty versus ethical and juridical bonds; the public versus the private; and the individual versus the community. Here, I attempt to formulate some essential principles that should guarantee humane measures for research on humans.

Current ethical issues in animal biotechnology

The present paper reviews the current status of opinion and debate regarding ethical issues in three broad categories of relevance to animal biotechnology. The first is scientific integrity, where the focus has been on scientific fraud and the integrity of the research process. The second concerns possible harms or risks to parties affected either directly by research (including animals themselves) or through the eventual commercialisation or development of products from animal biotechnology. The final category concerns a responsibility to serve as a guardian of the public interest with respect to application and development of technologies derived from new genetic sciences. It is plausible to see the scientific community as a whole having such a fiduciary obligation to the broader public in virtue of the technical complexity of the issues and owing to the public funding and institutional support for scientific research. The overall conclusion is that in the latter two categories especially, there is an urgent need for new participation in deliberative consideration of ethical issues by working scientists.

Retractions, press releases and newspaper coverage

OBJECTIVES

To explore how often newspapers cover the retraction of a medical journal article and whether newspaper coverage corresponds with the appearance of a press release about the retraction.

METHODS

Fifty citations were identified in PubMed that had been indexed with the Medical Subject Heading 'Retracted Publication'. Next, the archives of LexisNexis's 'Major Newspapers' and EurekAlert's press releases were searched to find references to those retracted publications.

RESULTS

Newspaper articles addressed exactly three of the 50 retracted publications, and press releases, exactly four of the 50 retracted publications. All three retracted publications that received newspaper coverage also had a press release. In other words, newspapers only covered a retraction that had been introduced by a press release.

CONCLUSION

One would expect that newspaper coverage would increase after a press release, but the suggested relationships among a medical journal article retraction, a press release and newspaper coverage should be further investigated. If the linkage suggested by the data of this study holds, and if newspaper coverage stimulates library patron interest, then a medical library might prepare itself for information requests following a press release.

Passage to Global Stem Cells

Cell of Cells The Global Race to Capture and Control the Stem Cell . By Cynthia Fox . Norton, New York, 2007. 558 pp. $26.95, C$35.50. ISBN 9780393058772.

Fox offers a timely and lively account of the science, history, politics, and sociology of stem cell research.

Exploitation of adherent neural stem cells in basic and applied neurobiology

Evidence for neurogenesis within the adult brain has challenged traditional views that this tissue is devoid of stem cell activity. This raises the possibility of introducing new cells through cell transplantation or stimulating endogenous neurogenesis as routes to treat disease and injury. Fetal and adult neural stem/progenitor cells can be isolated and expanded in vitro and might provide a cell source for such transplantations. Embryonic stem (ES) cells, which can generate any adult tissues, offer an alternative unlimited supply of neural tissue. We recently showed that both mouse and human ES cells can be converted to adherent neural stem (NS) cell lines [1] . Here we discuss the benefits of working with NS cell lines and how they might be exploited for studies of fundamental cellular processes, such as neuronal specification and differentiation. NS cells also serve as versatile models of disease processes, either through genetic manipulations or direct isolation from disease carriers and can be exploited in pharmaceutical drug screening. Longer term, NS cells offer an opportunity to rigorously test the efficacy of cell-based therapies and develop strategies for tissue engineering.

The proper conduct of research

Scientific misconduct has garnered recent attention by the media over scandals concerning falsification and fabrication of data surrounding potentially promising breakthroughs in stem-cell research, allegations of plagiarism at a U.S. university, and financial conflicts of interest between researchers and drug companies. While this makes for interesting copy, discussion of scientific fraud provides an excellent opportunity to review ethical standards for research and examine the conflicts that confront researchers today. This review specifically focuses on five areas that involve scientific integrity-plagiarism, falsification, fabrication, authorship, and conflict of interest-as well as nuances in each area that even senior investigators may not be aware of (e.g., self-plagiarism). The standards for ethical conductance of research discussed in this review are those set by many scientific, peer-reviewed journals and by federal and private granting agencies, and therefore it highlights the expectations and guidelines surrounding manuscript and grant submissions and review, and the consequences associated with violations. This review is intended to stimulate discussion among readers and assess what is necessary to become a good, competitive, but ethical researcher, especially in an era of shrinking financial resources for research.

Difficulties and possible solutions in the genetic management of mtDNA disease in the preimplantation embryo

Families who have had a child die of a severe, maternally inherited mitochondrial DNA (mtDNA) disease are usually desperate to avoid having further affected children. Here we discuss the problems of applying classical genetic management to mtDNA diseases (Poulton and Turnbull, 2000) and the biology underlying these problems. We explain why these disorders have lagged so far behind the genetics revolution. We then outline the directions in which management is likely to develop, including the use of preimplantation genetic diagnosis (PGD).

Acquiring human embryos for stem‐cell research

Human tissue engineering and regenerative medicine may be considerably advanced by embryonic stem-cell research and cell line development, to provide preventive means, cures and treatment strategies for a range of debilitating conditions and injuries. Research may result in embryos from which stem-cells are derived losing viability, which offends some religious convictions. The different status religions and laws may attribute to embryos serves different purposes and results from different approaches. Neither need depend on, nor impose itself on, the other. Embryos surplus to IVF patients' needs may be donated to research with appropriate consent. In some circumstances, it may be ethical to ask patients to make their fresh embryos available for research. Prohibitions against deliberately creating embryos for research purposes are common, but not universally adopted, and are being challenged. Women who donate ova require information about risks, which for women considering donation for research may not be balanced by compensating benefits.

Stem cell research: cloning, therapy and scientific fraud

Stem cell research has generated intense excitement, awareness, and debate. Events in the 2005-2006 saw the rise and fall of a South Korean scientist who had claimed to be the first to clone a human embryonic stem cell line. From celebration of the potential use of stem cells in the treatment of human disease to disciplinary action taken against the disgraced scientists, the drama has unfolded throughout the world media. Prompted by an image of therapeutic cloning presented on a South Korean stamp, a brief review of stem cell research and the events of the Woo-suk Hwang scandal are discussed.