Tag: gametes

Bioethics Blogs

The Very Early Embryo & Its Moral Signifiance

by Andrew J. Prunty

As technology and biological research continue to develop in the twenty-first century, it is necessary to address and further define the ethical considerations of embryonic research and the appropriate rights that may limit the extent of human research on zygotes, blastocysts, and fetal scientific advancement. Because the area of harvesting embryonic stem cells remains significantly undefined, both legally and morally, there are vastly different opinions between researchers and bioethicists, mainly because of ethical limitations, on the rights that should be granted to cells with the potential to develop into human beings and the consequences of neglecting significant scientific research or advancement.

Current laws in the United States differ at the federal and state level, but there is no consistency in recognizing human embryos as humans, or affording them the same legal rights granted to a child; in fact, legal precedent actually detracts certain rights from developing embryos, favoring a human’s ability to destroy a potential human being (i.e. Roe v. Wade[i]) or the categorization of embryos as property (i.e. Davis v. Davis[ii], A.Z. v. B.Z.[iii], Marriage of Dahl[iv], or Reber v. Reiss[v]). These case law samples suggest the courts’ inability to reach a conclusion as to what is the status of an embryo.

The debate is not only circumscribed to matters of research, but to fundamental controversial and intertwined issues of bioethics such as: when life begins, embryonic stem cells, fetal rights, abortion, et cetera. All these topics are contentious and when one topic arises, they begin to comingle.

The views, opinions and positions expressed by these authors and blogs are theirs and do not necessarily represent that of the Bioethics Research Library and Kennedy Institute of Ethics or Georgetown University.

Bioethics Blogs

The Ethics of In Vitro Gametogenesis

Françoise Baylis comments on the ethics of using gametes derived from human induced pluripotent stem cells for future human reproduction.

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A recent New York Times article, provocatively titled “Babies from Skin Cells? Prospect is Unsettling to Some Experts,” has once again drawn attention to controversial research by scientists at Kyushu University in Japan who succeeded in making fertile mouse pups using eggs created through in vitro gametogenesis (IVG). This is a reproductive technology that involves creating functional gametes (sperm and eggs) from induced pluripotent stem cells. Induced pluripotent stem cells are cells derived from adult body cells (such as skin cells) that have the ability to become other body cells including reproductive cells (sperm and eggs).

Supporters of this reproductive technology eagerly anticipate similar research in humans. Indeed, enthusiasts are quick to trumpet the potential benefits of in vitro gametogenesis. These benefits fall into three general categories.

First, we are told that research to derive human gametes from induced pluripotent stem cells is important for basic science. It will advance our understanding of gamete formation, human development, and genetic disease. In turn, this increased understanding will create new options for regenerative medicine.

Second, we are told that this research will allow clinicians to improve fertility services. For example, with in vitro fertilization (IVF), women typically have to undergo hormonal stimulation and egg retrieval. This can be onerous in terms of the time required for interviews, counseling, and medical procedures. It can also be harmful. Potential psychological harms include significant stress and its sequelae.

The views, opinions and positions expressed by these authors and blogs are theirs and do not necessarily represent that of the Bioethics Research Library and Kennedy Institute of Ethics or Georgetown University.

Bioethics News

Germline gene editing could soon reach the USA. What about the globally agreement that it should be prohibited?

“We’re very disappointed with the report. It’s really a pretty dramatic shift from the existing and widespread agreement globally that human germline editing should be prohibited”

On 14th February 2017, the National Academy of Science and the National Academy of Medicine in the United States (Washington, D.C.) issued a report drawn up by an international committee regarding the advisability of using gene editing techniques on the germline (gametes and preimplantation embryos).The report concludes that, “with stringent oversight, heritable germline gene editing clinical trials could one day be permitted for serious conditions”. Although they say that it is not yet the time and that much more research is required in this field, this report means a further step for gene editing in embryos.

germline-gene-editing-risks-reach-usaA step to

The embryos would not initially be implanted, as happens in England (See HERE), but would be used only in research. The following step would be their application in very severe clinical cases, as the report recommends. The fear of some scientists is that this will open the door to the production of so-called “designer babies”. “We’re very disappointed with the report. It’s really a pretty dramatic shift from the existing and widespread agreement globally that human germline editing should be prohibited”, says Marcy Darnovsky, executive director of the Center for Genetics and Society in Berkeley, California (See HERE).

Germline gene editing heritable risks; our bioethics assessment

The risks of genetically modifying the germline are unpredictable, and present the additional problem that the modifications will affect the entire organism and, therefore, will be transmitted from generation to generation.

The views, opinions and positions expressed by these authors and blogs are theirs and do not necessarily represent that of the Bioethics Research Library and Kennedy Institute of Ethics or Georgetown University.

Bioethics News

Germline gene editing could soon reach the USA. What about the globally agreement that it should be prohibited?

“We’re very disappointed with the report. It’s really a pretty dramatic shift from the existing and widespread agreement globally that human germline editing should be prohibited”

On 14th February 2017, the National Academy of Science and the National Academy of Medicine in the United States (Washington, D.C.) issued a report drawn up by an international committee regarding the advisability of using gene editing techniques on the germline (gametes and preimplantation embryos).The report concludes that, “with stringent oversight, heritable germline gene editing clinical trials could one day be permitted for serious conditions”. Although they say that it is not yet the time and that much more research is required in this field, this report means a further step for gene editing in embryos.

¿A step to designer babies?

The embryos would not initially be implanted, as happens in England (See HERE), but would be used only in research. The following step would be their application in very severe clinical cases, as the report recommends. The fear of some scientists is that this will open the door to the production of so-called “designer babies”. “We’re very disappointed with the report. It’s really a pretty dramatic shift from the existing and widespread agreement globally that human germline editing should be prohibited”, says Marcy Darnovsky, executive director of the Center for Genetics and Society in Berkeley, California (See HERE).

Germline gene editing heritable risks; our bioethics assessment

The risks of genetically modifying the germline are unpredictable, and present the additional problem that the modifications will affect the entire organism and, therefore, will be transmitted from generation to generation.

The views, opinions and positions expressed by these authors and blogs are theirs and do not necessarily represent that of the Bioethics Research Library and Kennedy Institute of Ethics or Georgetown University.

Bioethics Blogs

All we like SHEEFs, Part 2

Carrying on with last week’s musings…

In thinking further, I think my attempt was confused by conflating the moral status of a SHEEF—a synthetic human entity with embryo-like features, something more than a clump of cells of human origin, but less than a human being—with reasons why I might want to hold that nobody should ever make certain sorts of SHEEFs.

Again, SHEEFs are human, not non-human.  But they may not command a “right to life” in every instance.

I would return to a statement I made last week, that any totipotent human entity, that is, any human entity capable of developing into a full human being under the right circumstances, should be accorded a full human right to life from the moment he or she comes into existence.  We other humans ought to give him or her a chance to live, care for him or her as one of us, grant him or her any research protections extended to human research subjects in general, and so on.  So-called human “embryos in a dish” would be in this group.

The same cannot be said for individual human cells, including human gametes formed from cells like induced pluripotent stem cells.  There may be arguments why those ought not to be produced, but that is for another time.

I would not say that a laboratory-created or sustained human heart, for example, ought to be protected from instrumental uses, including destruction for the research enterprise.  I think I would want to argue that we humans ought not make such a thing as part of a human-non-human animal hybrid, but again, that’s a different argument.  

The views, opinions and positions expressed by these authors and blogs are theirs and do not necessarily represent that of the Bioethics Research Library and Kennedy Institute of Ethics or Georgetown University.

Bioethics Blogs

It takes a Village to…make… a Child?

Depending upon your political persuasion, Hillary Clinton is either famous or infamous for popularizing the concept that it takes a village to raise a child. Taking the village’s influence back to the point of conception, Assisted Reproductive Technologies (ART), specifically a potential novel combination of human Induced Pluripotential Stem Cells (hiPSCs) and in vitro gametogenesis (IVG), just might make it possible for that same village (that is, more than two parents) to actually make the child.

Jon Holmlund has written extensively in this blog regarding both the technique and ethical considerations of hiPSC and more recently human extended pluripotential stem cells (hESCs) (e.g. see here for a recent example). Roughly, hiPSCs/hESCs create stem cells (cells that have the potential to become any other cell in the human body) from common cells such as adult skin cells. IVG is the process that has the potential to change the hiPSCs/hESCs into gametes (eggs and sperm) which then can be combined via in vitro fertilization (IVF) to make a baby. If the process can be reliably perfected in humans, there would be no physical barrier for a single individual, non-fertile heterosexual couple, homosexual couple, or frankly any number of people to have a baby that is his/her/their genetic offspring (see summary here for ethical arguments fully supportive of these techniques and here for legal arguments both pro and con). We have already crossed into the concept of group parenting with maternal spindle cell transfer used to prevent mitochondrial disease (the so-called three parent babies). With IVG, we needn’t stop at just three parents (from the Palacios-Gonzalez et.

The views, opinions and positions expressed by these authors and blogs are theirs and do not necessarily represent that of the Bioethics Research Library and Kennedy Institute of Ethics or Georgetown University.

Bioethics News

Ethical questions about mitochondrial replacement in humans. Three parents babies

We thus consider it necessary to establish a moratorium on their use in humans, at least until more is known about these aspects. If this knowledge is obtained, ethical questions would still remain to be resolved, among which we consider the most relevant to be those related to the dignity and identity of the human embryo.

Children with two mothers and a father

In January 2017, the prestigious scientific journal Bioethics published a special edition dedicated to the ethical aspects of nuclear transfer techniques aimed at preventing the transmission of mitochondrial diseases, a topic that we have extensively addressed in our Observatory (see HERE).

Its editorial, Ethics of mitochondrial replacement, starts by referring to the recent birth of the first baby resulting from these techniques (see HERE). It then provides a brief description of the main characteristics of mitochondrial diseases, which are inherited exclusively from the mother. It explains that mothers who carry mutations in their mitochondrial DNA (mtDNA) face the uncertainty of not knowing if their genetic children will or will not inherit a serious mitochondrial disease. However the emergence of mitochondrial replacement techniques (MRT) offers these mothers hope, as healthy mitochondria from a donor are used to replace those of the mother. These techniques are maternal spindle transfer (MST) and pronuclear transfer (PNT), which consist, respectively, in removing the nucleus from a healthy egg or zygote, which will keep its mitochondria. The nucleus of the mother’s oocyte (patient or carrier of the mutation) or of another zygote obtained by fertilising the mothers egg is then transferred into the enucleated oocyte or zygote.

The views, opinions and positions expressed by these authors and blogs are theirs and do not necessarily represent that of the Bioethics Research Library and Kennedy Institute of Ethics or Georgetown University.

Bioethics Blogs

An Assessment of Mitochondrial Replacement Therapy

By: Alexa Woodward

Last year, a baby boy was born from an embryo that underwent mitochondrial replacement therapy (MRT). MRT was used to prevent this child from inheriting a mitochondrial disease from his mother, specifically infantile subacute necrotizing encephalomyelopathy – a disease that affects the central nervous system and usually results in death within the first few years of life. While controversial, assisted reproductive technologies (ARTs) such as MRT provide prospective parents with additional options and have the potential to improve the quality of human life by preventing disease.

This story is of bioethical interest because this technique results in germline modification, which is the alteration of DNA in the reproductive cells of humans that will be passed on to their offspring. Implementing MRT in humans has consequentially garnered much criticism, from simple health-related implications (such as unknown harms to potential offspring and eugenics concerns) to the futuristic next logical step of scientific intervention; directly editing the nuclear genome.

With MRT, modifications affect the mitochondrial genome (mtDNA), not the nuclear genome. Researchers emphasize the lack of bearing that mtDNA has on personal characteristics and the overall maintenance of “genetic integrity,” especially when compared to using the whole donor egg with an “unrelated” nuclear genome.1 Even so, additional concerns arise regarding the long-term anthropological effects, blurring the distinction between therapy and enhancement, and issues of resource allocation.

Mutations and deletions  in the mitochondrial genome can result in mitochondrial diseases affecting the neurological, musculoskeletal, cardiac, gastrointestinal, renal, and other systems, all of which are incurable.  MRT uses the intended parents’ nuclear DNA in conjunction with a donor’s mitochondria.

The views, opinions and positions expressed by these authors and blogs are theirs and do not necessarily represent that of the Bioethics Research Library and Kennedy Institute of Ethics or Georgetown University.

Bioethics News

US report gives cautious green light to gene editing

Human germline genome editing may be permissible following further research, according to a controversial report released on Tuesday by the US National Academy of Sciences (NAS) and the National Academy of Medicine.

The report outlines several criteria that should be met before allowing germline editing clinical trials to proceed. The criteria include the need for strict clinical oversight, credible pre-clinical data on risk and health benefits, and the assurance of “long-term multigenerational follow-up”.

Germline genome editing is an ethically contentious area of research, with many experts concerned that defective genes will be passed onto future generations. Unlike human genome editing, which takes place in children or adults and cannot be inherited, germline genome editing takes place in gametes or embryos and the altered genes can be inherited.

The committee acknowledged ethical concerns surrounding the research, but suggested an approach of “caution” rather than “prohibition”. The authors outlined a set of principles that should guide government research policy, including the ‘promotion of well-being’, ‘transparency’, and the exercise of ‘due care’. Trials should only be conducted for “treating or preventing serious disease or disabilities”.

Experts were divided over the report.

Eric Lander of the Broad Institute said that the report struck an appropriate balance between regulation and research: “They have closed the door to the vast majority of germline applications and left it open for a very small, well-defined subset. That’s not unreasonable in my opinion”.

Marcy Darnovsky of the Center for Genetics and Society was “deeply disappointed”: “Although [the recommendations] are couched in apparently cautionary language, they actually constitute a green light for proceeding with efforts to modify the human germline — that is, to engineer the genes and traits that are passed on to future children and generations.”

The views, opinions and positions expressed by these authors and blogs are theirs and do not necessarily represent that of the Bioethics Research Library and Kennedy Institute of Ethics or Georgetown University.

Bioethics Blogs

Ethical reflection on the latest biomedical experiments by Juan Carlos Izpisua and his group

Juan Carlos Izpisua biomedical experiments. They present serious ethical problems primarily because some of them use human embryonic stem cells

pdfOver the last few days, some of the biomedical experiments conducted by Juan Carlos Izpisua and his group — in which researchers from several Spanish universities take part — have been widely reported by various media.

Let us say at the outset that we see no need to highlight the biomedical importance of these experiments (some of which we would dare describe as spectacular), as this has already been abundantly emphasised by the media. Quite another matter is the possibility of being able to use what they have achieved in human medicine, which could take several years.

The bioethical aspects of these experiments have scarcely been addressed, however, and we believe they merit consideration.

Before we go any further, and in order to structure this report, the experiments by Izpisua to which we are referring should be divided into three groups. Concisely (although we will refer to this in more detail below) they are: a) to create quasi-human organs in animals, to be ultimately used for clinical transplants; b) to modify the CRISPR technique that offers so many biomedical possibilities, to make it more efficient, and c) to apply cell reprogramming “in vivo”, to try to rejuvenate a group of experimental animals.

  1. To create quasi-human organs in animals.

chimeraThese experiments were first reported in an article published in Nature in May 2015. They essentially consist in injecting human embryonic stem cells into mice so that they can generate quasi-human organs, since the human cells injected into the animal will produce organs with a genome that is very close to the human one.

The views, opinions and positions expressed by these authors and blogs are theirs and do not necessarily represent that of the Bioethics Research Library and Kennedy Institute of Ethics or Georgetown University.