Cryopreservation of human embryos remains, in many jurisdictions, a critical component of the use of the technology of in vitro fertilisation in assisted reproduction. However, although the reasons for the freezing of reproductive material—such as cost effectiveness and reducing risks of IVF—are a constant across jurisdictions, the desirable length of storage remains subject to ongoing regulatory debate. Internationally embryo storage limits are variable. This article features data from a recent Australian research project which explores individual attitudes, desires (...) and understandings of law of IVF patients who had or who have embryos in storage. This article uses interviews from the study to argue that storage limits, like any apparently neutral regulatory tool, apply unequally causing unintended physical, mental and emotional harm—particularly to women. This analysis of storage limits exposes the interaction of time, science and law to create, apply and enforce norms and practices of ‘natural’ embryo storage, suggesting that the imposition of inflexible legislative restrictions upon embryo storage are socially contingent and value laden rather than ‘natural’ or ‘scientific’. This outcome has relevance to wider debates over assisted reproduction policies, suggesting that legal frameworks should adopt more flexibility in application to the patients who use this technology. (shrink)

Genetic relatedness poses significant challenges to traditional practices of medical ethics as concerns the biobanking of human biological samples. In this paper, we first outline the ethical challenges to informed consent and confidentiality as these apply to human biobanks, irrespective of the type of tissue being stored. We argue that the shared nature of genetic information has clear implications for informed consent, and the identifying nature of biological samples and information has clear implications for promises of confidentiality. Next, with regard (...) to the special case of biobanking human embryos and eggs, we consider issues arising from: first, the type of tissues being stored; second, the use to which these tissues are put; and third, how this plays out given the shared and identifying nature of these tissues. Specifically, we examine the differences between human bodily tissues and human reproductive tissues focusing on the assumed potential of the reproductive tissues and on the possible greater emotional attachment to these tissues because of their real and imagined kinship. For some donors there may be a sense of family connection with embryos and eggs they once thought of as ‘children-in-waiting’. Finally, we conclude by considering the implications for ethical practice. (shrink)

Guidelines on embryo storage prioritise 'respect for the embryo' above the wishes of the women whose labour and tissue have gone into creating the embryo in the first place, effectively making women and the female body disappear. In this article I draw a parallel between this phenomenon relating to embryo storage and other instances of a similar phenomenon that I have called 'the lady vanishes', particularly in stem cell and 'mitochondrial transfer' research. I suggest (...) that a modified property regime could protect women's interests in embryo storage, making a parallel with the Yearworth case, in which it was recognised that men had limited but actionable interests in their stored sperm.. (shrink)

This article discusses when it is ethically acceptable to withdraw consent for the storage and use of embryos and gametes. Currently, the law in the UK states that consent to use of a gamete or embryo can be withdrawn up to the point of the embryo's transfer to the recipient's uterus or when the gamete is used in providing treatment services; that is, the ‘point of no return’. In this article, we will consider other points of no (...) return and argue that having a single point of no return, a one size fits all form of consent can, in some cases, lead to restrictions on individuals’ autonomy and cause particular types of harm. Therefore, having different points of no return that fit different circumstances could extend autonomy and allow people to enter into agreements that are tailored more to their own particular needs and circumstances. (shrink)

As is the case around the globe, South African fertility clinics face an ever‐expanding problem: what to do with the growing number of surplus cryopreserved embryos. Fertility clinics remain hesitant to destroy these abandoned embryos, partly because of concerns about the legal ramifications. This article clarifies the legal position in South Africa and offers practical recommendations to assist fertility clinics in managing abandoned embryos. In sum, fertility clinics cannot deem embryos as abandoned and discard them if fertility patients fail to (...) respond to a notice that the embryo storage agreement is about to expire. However, if there is non‐payment for embryo storage by fertility patients and the fertility clinic has informed the fertility patients of other options available to them with respect to their embryos, and there is still no response, the fertility clinic is legally entitled – and legally obliged – to discard the embryos. (shrink)

Many of the thousands of human embryos currently in cryogenic storage will sooner or later be discarded, often after being experimented upon. Others will remain in storage indefinitely, left there by parents who have no plans either to bring them to term or to offer them for adoption. These facts, coupled with a commitment to the basic moral equality of all human beings at all stages of development, generate a pressing question: What should be done for these embryos (...) whose vital activities have been suspended and whose futures look so bleak? This paper offers a case that allows some of these cryogenically stored embryos to thaw and die, allows disposal of their remains in a manner that reflects their status, and is morally acceptable in that it is consistent with the principles that many accept as governing the removal of life-sustaining treatment in end-of-life cases. (shrink)

There are substantial numbers of frozen embryos in storage that will not be used by those who produced them for their own fertility treatment. One option for such embryos is to donate them to others to use in their fertility treatment. There has been considerable debate about how this process should be organized. In the US, there are embryo adoption programmes that mediate between those relinquishing embryos and potential recipients. This is a form of conditional embryo donation, (...) where the relinquishing couple can choose the recipient of their embryo. This article examines the ethical debate over conditional embryo donation for family building and explores the question of whether those who have unused frozen embryos should be able to determine who receives their embryos. The main objections to conditional embryo donation are examined: first, the embryo is not a person and therefore such concern over the placement of an embryo is unwarranted; secondly, potential donors might impose morally problematic conditions on who should receive their embryo; and thirdly, there are practical difficulties regarding organizational arrangements and the associated costs involved. It will be concluded that these objections can be countered and that if people wish to donate and receive embryos in this way there is no ethical objection to them doing so. (shrink)

BackgroundPrevious studies have found that the decision-making process for stored unused frozen embryos involves much emotional burden influenced by socio-cultural factors. This study aims to ascertain how Japanese patients make a decision on the fate of their frozen embryos: whether to continue storage discard or donate to research.MethodsTen Japanese women who continued storage, 5 who discarded and 16 who donated to research were recruited from our infertility clinic. Tape-recorded interviews were transcribed and analyzed for emergent themes.ResultsA model of (...) patients’ decision-making processes for the fate of frozen embryos was developed, with a common emergent theme, “coming to terms with infertility” resulting in either acceptance or postponing acceptance of their infertility. The model consisted of 5 steps: 1) the embryo-transfer moratorium was sustained, 2) the “Mottainai”- embryo and having another child were considered; 3) cost reasonability was taken into account; 4) partner’s opinion was confirmed to finally decide whether to continue or discontinue storage. Those discontinuing, then contemplated 5): the effect of donation. Great emotional conflict was expressed in the theme, steps 2, 4, and 5.ConclusionsPatients’ 5 step decision-making process for the fate of frozen embryos was profoundly affected by various Japanese cultural values and moral standards. At the end of their decision, patients used culturally inherent values and standards to come to terms with their infertility. While there is much philosophical discussion on the moral status of the embryo worldwide, this study, with actual views of patients who own them, will make a significant contribution to empirical ethics from the practical viewpoint. (shrink)

Theory of health care ethics -- Principles of health care ethics -- The moral status of gametes and embryos : storage and surrogacy -- The ethical challenges of the new reproductive technology -- Ethics and aging in America -- -- Healthcare ethics committees : roles, memberships, structure, and difficulties -- Ethics in the management of health information systems -- Technological advances in health care : blessing or ethics nightmare? -- Ethics and safe patient handling and mobility -- Spirituality and (...) healthcare organizations -- A new era of health care : the ethics of healthcare reform -- Health inequalities and health inequities -- The ethics of epidemics -- Ethics of disasters : planning and response -- Domestic violence : changing theory, changing practice -- Looking toward the future. (shrink)

To whom do sperm and ova belong? Few tissues are produced by the human body with more waste than the germ cells. Yet dominion over the germ cells, and over the early embryo that results from their union in vitro, is behind much of the emotion that modern reproductive intervention can engender. The germ cells differ from other human tissues that can be donated or transplanted because they carry readily utilizable genetic information. Eventual expression of the germ cells' genetic (...) potential is the legitimate concern and responsibility of their donors, although in the right circumstances the responsibility can by agreement be entrusted to institutions administering gamete or embryo donor programmes; these institutions, in turn, may need to assume responsibility for decisions if, in the case of embryo storage, the wishes of the two donors conflict. The fact of sperm and ovum ownership (and the genetic potential that goes with it) before individuals part with these tissues is beyond dispute. Some contentious issues may be clarified if this area of human dominion, namely control over genetic expression among offspring, is acknowledged to be the legitimate persisting concern of those who have produced sperm and ova after storage commences. (shrink)

Recent decades have seen the facilitation of unconventional or even extraordinary reproductive endeavours. Sperm has been harvested from dying or deceased men at the request of their wives; reproductive tissue has been surgically removed from children at the request of their parents; deceased adults’ frozen embryos have been claimed by their parents, in order to create grandchildren; wombs have been transplanted from mothers to their daughters. What is needed for requests to be honoured by healthcare staff is that they align (...) with widely shared expectations about what people’s reproductive potential ought to be, what marital relationships ought to result in, and which kinds of ties are desirable between parents and children. Costly and invasive technologies are not considered excessive when they are used to support the building of appropriate families. However, deviations from dominant reproductive norms, even if technologically simple and convenient to the participants, are unlikely to receive support. In this paper, we offer examples of such deviations and explore their implications. If reproduction is important as a way of creating genetic relationships, should reproductive material in storage be offered to genetic relatives other than the people from whom it originated? And if parents are allowed to have reproductive material collected from their offspring, or even to use it to create babies, should offspring likewise be allowed to use their parents’ reproductive material? We tackle these questions and suggest ways in which interests in genetic ties could be operationalised in a more coherent and less-invasive manner than they currently are. (shrink)

The Department of Health's Review of the Human Fertilisation and Embryology Act 1990 is a comprehensive public consultation on the regulation of the storage and use of gametes and embryos for fertility treatment and research in the UK. The consultation considers a range of issues, including the model and scope of regulation and proposals for a single body, the Regulatory Authority for Tissue and Embryos, to replace both the Human Fertilisation and Embryology Authority and the Human Tissue Authority by (...) April 2008. The Department of Health published its report on the consultation in March 2006, and this is discussed here in relation to both the support and criticisms of the model and scope of the current and proposed regulatory frameworks, particularly with regard to policy decision-making by bodies such as HFEA and RATE. (shrink)

Oncofertility is one of the 9 NIH Roadmap Initiatives, federal grants intended to explore previously intractable questions, and it describes a new field that exists in the liminal space between cancer treatment and its sequelae, IVF clinics and their yearning, and basic research in cell growth, biomaterials, and reproductive science and its tempting promises. Cancer diagnoses, which were once thought universally fatal, now often entail management of a chronic disease. Yet the therapies are rigorous, must start immediately, and in many (...) cases result in premature failure of the body's reproductive ability. In women, this loss is especially poignant; unlike the routine storage of sperm, which is done in men and boys facing similar treatment decisions, freezing oocytes in anticipation of fertility loss is not possible in most cases, and creating an embryo within days of diagnosis raises significant moral, social and medical challenges. Oncofertility is the study of how to harvest ovarian tissue in women facing cancer to preserve their gametes for future use with IVF, thus allowing the decisions about childbearing to be deferred and reproductive choices to be preserved. The research endeavor uses the capacity of the ovarian follicle to produce eggs in vitro . Developing the human follicle to ovulate successfully outside the body is scientifically difficult and ethically challenging. Infertility is linked to long-standing religious and moral traditions, and is intertwined with deeply contentious social narratives about women, families, illness and birth. Is the research morally permissible? Perhaps imperative if understood as a repair from iatrogenic harms? How are considerations of justice central to the work? How will vulnerable subjects be protected? What are the moral implications of the work for women, children and families? What are the implications for society if women could store ovarian tissue as a way of stopping the biological clock? What are the moral possibilities and challenges if eggs can be produced in large quantities from a stored ovarian tissue? (shrink)

The UK Human Fertilisation and Embryology Authority was right to permit tissue typing preimplantation genetic diagnosisOn July 21 2004, the Human Fertilisation and Embryology Authority , Britain’s regulatory agency for reproductive technologies, revised its policy on preimplantation genetic diagnosis for tissue typing.1,2 The authority of the HFEA to enact such a policy was affirmed by the UK’s highest court, the House of Lords, on April 28 2005.3 Preimplantation genetic diagnosis combines in vitro fertilisation with genetic testing. In PGD, embryos generally (...) undergo biopsy prior to the eight cell stage, followed by genetic testing for a particular trait. Tissue typing PGD is done to identify an embryo that is tissue matched for a child suffering from a severe disease requiring bone marrow or cord blood stem cell transplantation and for whom no living donor exists. This procedure was first performed in 2000.4 Precise matching of tissue types is critical to successful tissue transplant, and the donors of such tissues are often referred to as “saviour siblings”.Where a tissue matched individual already exists, extracting bone marrow from that individual or collecting cord blood already in storage, rather than creating a match, presents the most immediate treatment alternative. Bone marrow donation from adults or other medically competent individuals is not generally ethically contested, and bone marrow donation from medically incompetent individuals is also permissible under certain conditions.5 Where no living tissue donor exists, however, intentionally creating a donor through tissue typing PGD is among a short list of possible treatment options.The July HFEA policy change makes PGD licensable in cases where tissue typing is the only purpose of testing. Previously, PGD was licensable in the UK only for disease testing, and tissue typing PGD was permissible only when …. (shrink)

Oncofertility is one of the 9 NIH Roadmap Initiatives, federal grants intended to explore previously intractable questions, and it describes a new field that exists in the liminal space between cancer treatment and its sequelae, IVF clinics and their yearning, and basic research in cell growth, biomaterials, and reproductive science and its tempting promises. Cancer diagnoses, which were once thought universally fatal, now often entail management of a chronic disease. Yet the therapies are rigorous, must start immediately, and in many (...) cases result in premature failure of the body's reproductive ability. In women, this loss is especially poignant; unlike the routine storage of sperm, which is done in men and boys facing similar treatment decisions, freezing oocytes in anticipation of fertility loss is not possible in most cases, and creating an embryo within days of diagnosis raises significant moral, social and medical challenges. Oncofertility is the study of how to harvest ovarian tissue in women facing cancer to preserve their gametes for future use with IVF, thus allowing the decisions about childbearing to be deferred and reproductive choices to be preserved. The research endeavor uses the capacity of the ovarian follicle to produce eggs in vitro. Developing the human follicle to ovulate successfully outside the body is scientifically difficult and ethically challenging. Infertility is linked to long-standing religious and moral traditions, and is intertwined with deeply contentious social narratives about women, families, illness and birth. Is the research morally permissible? Perhaps imperative if understood as a repair from iatrogenic harms? How are considerations of justice central to the work? How will vulnerable subjects be protected? What are the moral implications of the work for women, children and families? What are the implications for society if women could store ovarian tissue as a way of stopping the biological clock? What are the moral possibilities and challenges if eggs can be produced in large quantities from a stored ovarian tissue? (shrink)

Iran is the only Muslim country that has legislation on embryo donation, adopted in 2003. With an estimated 10–15% of couples in the country that are infertile, there are not any legal or religious barriers that prohibit an infertile couple from taking advantage of Assisted Reproductive Technologies (ARTs). Although all forms of ARTs available in Iran have been legitimized by religious authorities, there is a lack of legislation in all ARTs except embryo donation. By highlighting ethical issues in (...) embryo donation, the paper presents a critical review of the Act of Embryo Donation in Iran. The paper argues that the Act does not provide enough safeguards for the future child and assurance for the safety of the donated embryos. It also does not restrict embryo donation to surplus embryos from infertile couples and is silent about the number of embryos that could be donated by each couple as well as the number of recipients for donated embryos by a couple. The Act is also silent about the issues of genetic linkage (nasab) and heritage which are challenging issues, especially in a conservative Islamic society. As a result, the future child may not inherit from their birth parents, as it is not required by the Act, or from the genetically related parents under the anonymity policy. Finally there is no standard national protocol or guidelines to evaluate the safety of the donated embryos. The paper concludes that despite its benefits, the Act lacks clarity, and it is subject to misunderstanding and confusion. (shrink)

Rob Lovering has developed an interesting new critique of views that regard embryos as equally valuable as other human beings: the moral argument for frozen human embryo adoption. The argument is aimed at those who believe that the death of a frozen embryo is a very bad thing, and Lovering concludes that some who hold this view ought to prevent one of these deaths by adopting and gestating a frozen embryo. Contra Lovering, we show that there are (...) far more effective strategies for preserving the lives of frozen embryos than adoption. Moreover, we point out that those who regard the deaths of frozen embryos as a very bad thing will generally regard the deaths of all embryos as a very bad thing, whether they are discarded embryos, aborted embryos or embryos that spontaneously abort. This entails these other embryos must be taken into account when considering moral obligations, as well as other human lives at risk from preventable causes. (shrink)

It now seems technically feasible to culture human embryos beyond the “fourteen‐day limit,” which has the potential to increase scientific understanding of human development and perhaps improve infertility treatments. The fourteen‐day limit was adopted as a compromise but subsequently has been considered an ethical line. Does it remain relevant in light of technological advances permitting embryo maturation beyond it? Should it be changed and, if so, how and why? What justifications would be necessary to expand the limit, particularly given (...) that doing so would violate some people's moral commitments regarding human embryos? Robust stakeholder engagement preceded adoption of the fourteen‐day limit and should arguably be part of efforts to reassess it. Such engagement could also consider the need for enhanced oversight of human embryo research. In the meantime, developing and implementing reliable oversight systems should help foster high‐quality research and public confidence in it. (shrink)

In 1990, J. L. Krivine introduced the notion of storage operator to simulate “call by value” in the “call by name” strategy. J. L. Krivine has showed that, using Gödel translation of classical into intuitionistic logic, one can find a simple type for the storage operators in AF2 type system. This paper studies the ∀-positive types and the Gödel transformations of TTR type system. We generalize by using syntactical methods Krivine's theorem about these types and for these transformations. (...) We give a proof of this result in the case of the type of recursive integers. (shrink)

Recent scientific advances have indicated that it may be technically feasible to sustain human embryos in vitro beyond 14 days. Research beyond this stage is currently restricted by a guideline known as the 14-day rule. Since the advances in embryo culturing there have been calls to extend the current limit. Much of the current debate concerning an extension has regarded the 14-day rule as a political compromise and has, therefore, focused on policy concerns rather than assessing the philosophical foundations (...) of the limit. While there are relevant political considerations, I maintain that the success of extension arguments will ultimately depend on the strength of the justifications supporting the current 14-day limit. I argue that the strongest and most prevalent justifications for the 14-day rule—an appeal to individuation and neural development—do not provide adequate support for the limit of 14 days. I instead suggest that an alternative justification based on sentience would constitute a more defensible basis for embryo protection and that a consideration of such grounds appears to support an amendment to the current limit, rather than the retention of it. While these conclusions do not establish conclusively that the current limit should be extended; they do suggest that an extension may be warranted and permissible. As such, this paper offers grounds on which a reassessment of the 14-day rule may be justified. (shrink)

I defend the argument that if embryo loss in stem cell research is morally problematic, then embryo loss in in vivo conception is similarly morally problematic. According to a recent challenge to this argument, we can distinguish between in vivo embryo loss and the in vitro embryo loss of stem cell research by appealing to the doctrine of double effect. I argue that this challenge fails to show that in vivo embryo loss is a mere (...) unintended side effect while in vitro embryo loss is an intended means and that, even if we refine the challenge by appealing to Michael Bratman's three roles of intention, the distinction is still unwarranted. (shrink)

How has the storage of information shaped human cognition? We bring together current advances in cognitive science, the neurobiology of memory, and archaeology to explore how storage of information affects consciousness. These fields strongly suggest that the increase in storage of information in the environment – which we call exosomatic storage of information – may have led to changes in human consciousness and human neurophysiology over time. To bring these findings together conceptually, we develop what we (...) call a dialectical model of the relationship between storage of information and the development of human consciousness. Using the system of dialectic philosophy, we put forward that (a) environmental changes, consciousness, and neurophysiology develop together, (b) these changes were irreversible, (c) quantitative increases in exosomatic storage of information may have led to qualitative changes in human consciousness and neurophysiology, (d) these changes in turn affected how we see ourselves. Indeed, our capacity to store information exosomatically distinguishes us from other animals, and may be a key attribute of our self-awareness and therefore self-consciousness. Because metaphors are central to human thought and can help structure scientific inquiry, we illustrate our model using a metaphor of drops of silver on the back of a glass, eventually making a mirror—where successive quantitative change leads to an irreversible qualitative development in human consciousness. The dialectic model can offer new insights into the co-evolution of material culture and human beings through its broader philosophical foundations and explanatory power. (shrink)

The recent publications reported in 2022 reveal the possibility of obtaining mouse embryos without the need for egg or sperm. These ‘artificial embryos’ can recapitulate some stages of development ex utero – from neurulation to organogenesis – without implantation. Synthetic mouse embryos might serve as a valuable model to gain further insights into early developmental stages. Indeed, it is expected for these models to be replicated by employing human cells. This promising research raises ethical issues and expands the horizon of (...) ethics in regard to the development of the human embryo. From this point of view, we state some of the new open venues for bioethical research. (shrink)

Contemporary philosophical discussion on human embryonic stem cell research has focused primarily on the metaphysical and meta-ethical issues suchresearch raises. Though these discussions are interesting, largely ignored are arguments rooted in the secular research ethics tradition already informing humansubject research. This tradition countenances the notion of vulnerability and that vulnerable human subjects (of which human embryos are likely members)ought to be protected from research-related harms. This is the basic idea behind the argument from vulnerability, and it enjoys prima facie plausibility. (...) This articlepresents the vulnerability argument and then focuses critically on several lines of attack including: (1) twinning and totipotency arguments, (2) embryo-rescuearguments, and (3) natural loss arguments. The article concludes that there is no good defeater for the vulnerability argument, and, therefore, we have undefeated reasons for protecting human embryos from research related harms. (shrink)

In the debate regarding the moral status of human embryos, the Embryo Rescue Case has been used to suggest that embryos are not rightholders. This case is premised on the idea that in a situation where one has a choice between saving some number of embryos or a child, it seems wrong to save the embryos and not the child. If so, it seems that embryos cannot be rightholders. In this paper, I argue that the Embryo Rescue Case (...) does not independently show that embryos are not rightholders. (shrink)

This paper is based on linked qualitative studies of the donation of human embryos to stem cell research carried out in the United Kingdom, Switzerland, and China. All three studies used semi-structured interview protocols to allow an in-depth examination of donors’ and non-donors’ rationales for their donation decisions, with the aim of gaining information on contextual and other factors that play a role in donor decisions and identifying how these relate to factors that are more usually included in evaluations made (...) by theoretical ethics. Our findings have implications for one factor that has previously been suggested as being of ethical concern: the role of gratitude. Our empirical work shows no evidence that interpersonal gratitude is an important factor, but it does support the existence of a solidarity-based desire to “give something back” to medical research. Thus, we use empirical data to expand and refine the conceptual basis of bioethically theorizing the IVF–stem cell interface. (shrink)

The main objection to human embryonic stem cell research is that it involves killing human embryos, which are essentially beings of the same sort that you and I are. This objection presupposes that we once existed as early embryos and that we had the same moral status then that we have now. This essay challenges both those presuppositions, but focuses primarily on the first. I argue first that these presuppositions are incompatible with widely accepted beliefs about both assisted conception and (...) monozygotic twinning. I then argue that we never existed as embryos. If this last claim is right, killing an embryo does not kill someone like you or me but merely prevents one of us from existing. (shrink)

In 1990, J. L. Krivine introduced the notion of storage operator to simulate, for Church integers, the “call by value” in a context of a “call by name” strategy. In the present paper we define for every λ-term S which realizes the successor function on Church integers the notion of S-storage operator. We prove that every storage operator is an S-storage operator. But the converse is not always true.

The “Embryo Rescue Case” (ERC) refers to a thought experiment that is used to argue against the view that embryos have a right to life (i.e. are persons). I will argue that cognitive science undermines the intuition elicited by the ERC; I will show that whether or not embryos have a right to life, our mental tools will make it very difficult to believe that embryos have said right. This suggests that the intuition elicited by the ERC is not (...) truth indicative. The upshot of this is that we have an undercutting defeater for our intuition that embryos do not have a right to life. (shrink)

We have discovered that a single sperm protein, phospholipase C‐zeta (PLCζ), can stimulate intracellular Ca2+ signalling in the unfertilized oocyte (‘egg’) culminating in the initiation of embryonic development. Upon fertilization by a spermatozoon, the earliest observed signalling event in the dormant egg is a large, transient increase in free Ca2+ concentration. The fertilized egg responds to the intracellular Ca2+ rise by completing meiosis. In mammalian eggs, the Ca2+ signal is delivered as a train of long‐lasting cytoplasmic Ca2+ oscillations that begin (...) soon after gamete fusion and persist beyond the completion of meiosis. Sperm PLCζ effects Ca2+ release from egg intracellular stores by hydrolyzing the membrane lipid PIP2 and consequent stimulation of the inositol 1,4,5‐trisphosphate (InsP3) receptor Ca2+‐signalling pathway, leading to egg activation and early embryogenesis. Recent advances have refined our understanding of how PLCζ induces Ca2+ oscillations in the egg and also suggest its potential dysfunction as a cause of male infertility. (shrink)

Are embryos deserving of moral consideration in our actions? A standard view suggests that embryos are considerable only if they have interests. One argument for embryonic interests contends that embryos are harmed by death because they are deprived of valuable future lives as adult persons. Some have challenged this argument on the grounds that embryos aren’t identical to adults: either due to the potential for embryos to twin or because we do not exist until the fetus develops consciousness. These arguments (...) fail to show that embryos do not have future adult lives. There is a better reason to think that embryos cannot have interests; namely, because they are not capable of having desires. Others have held this view but have not sufficiently justified it. The justification lies in the fact that the capacity for desires is necessary to make sense of the normativity of interests. (shrink)

At a time when bioethical issues are at the top of public and political agendas, there is a renewed interest in representations of the embryo in various religious traditions. One of the major traditions that have contributed to Western representations of the embryo is the Jewish tradition. This tradition poses some difficulties that may deter scholars, but also presents some invaluable advantages. These derive from two components, the search for limits and narrativity, both of which are directly connected (...) with the manner in which Jewish tradition was constructed in Antiquity. The article accomplishes three goals: • To introduce some central elements in ancient Rabbinic literature on the subject of the embryo and its representation; • To present this body of literature as clearly as possible, noting some of the difficulties encountered by scholars who engage in its study; • To explain how the literature’s textuality came about, examining the particular sociopolitical circumstances of Judaism at that time, including the reasons for the delay in the production of scientific texts, transmitted as such, as compared to other philosophical or religious traditions. The claim is that these circumstances engendered a tradition peculiarly relevant for the study and teaching of medical ethics today. (shrink)

What makes something an embryo—as opposed to what is actually, and not just in biotech parlance, a collection of cells? This question has come to the fore in recent years with proposals for producing embryonic stem cells for research. While some of those opposed to use of standard embryonic stem cells emphasise that adult cells have a clinical track record, others argue that there may be further benefits obtainable from cells very like those of embryos, provided such cells can (...) be derived in new ways. Rather than deriving them in ways that kill or otherwise endanger a living human embryo, they could be obtained from an entity that merely resembles a human embryo sufficiently closely for its cells to be of use. Such an entity might be created after introducing genetic changes to an ovum before it is activated by, for example, a cloning-type procedure, such that a gene essential to embryogenesis will be either absent, blocked in its expression, or overexpressed.1,2 The claim is that the ovum could be made to give rise to embryonic stem cells—mere living parts—without ever giving rise to a whole embryo, who is killed to obtain them. Whereas cloning “proper” winds back the specialisation of the cell nucleus to a point where a whole embryo is formed who has not yet specialised its cells, oocyte-assisted reprogramming , it is claimed, would wind back the specialisation merely to an intermediate point at which no embryo is created. Other methods proposed for deriving pseudoembryonic cells include parthenogenesis, in which an ovum is activated without a sperm, or even the insertion of an adult cell nucleus.1MORAL STATUS OF THE EMBRYOIn this paper, I assume that a genuine …. (shrink)

The emergence of ethical controversy -- First embryo research regimes -- The ethics of embryonic stem cell research -- Stem cell and cloning politics.

The stereotyped pattern of cell commitments during leech embryogenesis is described. The nature of cell commitments during segmentation differs significantly between leech and fruit fly. Despite the constancy of cell fate assignments in normal development, ablation experiments show that cell interactions are essential in setting some of these commitments. Interacting cells follow a positionally determined hierarchy of fate choices. For other cells, which appear to have fates fixed from birth, the possibility of determinative interactions between mother and daughter cells is (...) discussed. (shrink)

It is widely held that (1) there are autonomous levels of organization above that of the macromolecule and that (2) at least sometimes macromolecular processes are best explained in terms of such autonomous kinds. I argue that molecular developmental biology honors neither of these claims, and I show that the only way they can be rendered consistent with a minimal physicalism is through the adoption of controversial claims about causation and explanation which undercut the force of these two antireductionism claims.

Development of the nematode Caenorhabditis elegans has been described completely on a cell‐by‐cell basis. In an invariant pattern five somatic founder cells and the primordial germ cell are generated within the first hour after the onset of cleavage. Using a laser microbeam for manipulation of individual blastomers several aspects of early embryogenesis have been investigated, including the expression of cellular polarity, the localization of lineage‐specific cleavage potential, the necessity for early cell–cell interaction, and the control of differential cell‐cycle timing. The (...) experiments demonstrate the central importance of a correct partitioning of cytoplasmic components during early embryogenesis and suggest a stepwise, binary segregation mechanism associated with the unequal cleavages in the germline. (shrink)