Response to Commentators on “Rescuing Human Embryonic Stem Cell Research: The Blastocyst Transfer Method”
by S. Matthew Liao
2005. The American Journal of Bioethics 5(6):W10

I would like thank all the commentators for their insightful points. I have learned a great deal from them and I hope that the following response clarifies my arguments.

In my article, I considered the objection that the Blastocyst Transfer Method (BTM) might violate the embryo’s autonomy as a person (Liao 2005b). I argued that one way to meet this Autonomy Objection is to recognize that the autonomy of a person is sometimes violable if an action would bring very little or no harm to that person but would greatly benefit others. Fritz Allhoff argues that this response is unlikely to persuade an “absolutist deontologist,” because the absolutist deontologist would simply hold that the autonomy of a person is always inviolable. Allhoff concludes that BTM therefore does not circumvent “the moral hazards of conventional stem cell research” (Allhoff 2005, 30).

Although I do think that my argument illustrates the plausibility of a non-absolutist position, Allhoff is correct that this argument will not persuade an absolutist deontologist. However, the conclusion Allhoff draws from this—that BTM does not circumvent “the moral hazards of conventional stem cell research” (Allhoff 2005, 30)—does not follow. This is because I gave two arguments in response to the Autonomy Objection, including the argument that consent from a person typically is not necessary if the intended action is to benefit the person, and if the benefit is deemed to outweigh the potential harm. A typical example of this is treating an unconscious person who needs a life-saving operation but who has not consented to the procedure. Since BTM can be done solely out of the intention to benefit the tampered embryos, this means that consent by the embryos would not be necessary since, like the unconscious person who needs a life-saving operation, the intended action is to benefit the embryo and the benefit is deemed to outweigh the harm. Allhoff also uses an example similar to my unconscious person example to suggest that consent is not necessary in such a case. Hence, we can presume that this second argument would be acceptable even to an absolutist deontologist.

Søren Holm argues that BTM cannot save hESC research because “Liao clearly realizes the BTM can only fully meet the embryoist objection if it is completely risk free for the embryo,” (Holm 2005, 20) and BTM is never risk free. Contrary to Holm’s statement, I have not claimed that BTM has to be “risk free” in order to satisfy an embryoist, nor do I believe this. Vaccinations such as polio shots are not “risk free” in that there is a chance they can result in deaths. Yet, embryoists would typically not object to these procedures. The best explanation is that embryoists do not require that these procedures be risk free; what they require is that, all other things being equal, the benefit of the risk of a procedure outweighs the cost. Given that BTM can be done in a way in which the benefit of the risk outweighs the cost, BTM would meet the requirements of these embryoists.

Zubin Master argues that “it may never be possible to reduce the invasiveness of the BTM to safety standards compared to preimplantation genetic diagnosis,” (Master 2005, 27) and therefore BTM treats the embryo as a mere means, since the risk to it outweighs the benefit. Master and I agree that, if the risk of BTM outweighs the benefit to the embryo, then BTM is not a viable alternative solution to hESC research. We disagree about the level of possible risk involved in BTM. Master says that “the removal of any number of cells from the inner cell mass may result in formation of morphological abnormalities in the embryo despite evidence from early bovine embryo bisections.” But Master does not explain why “evidence from early bovine embryo bisections” should be discounted. As I discussed, there has been no evidence for increased incidence of birth defects or abnormal offspring from these bisection procedures. Moreover, these procedures are much more invasive than BTM, since they involve cutting the blastocyst in half with a microscalpel. Hence, Master’s conclusion that BTM treats the embryo as a mere means need not follow.

Carolyn McLeod is concerned about what she calls the “stork phenomenon,” which is the failure explicitly to note that women are the ones who would bear a significant portion of the burden of fertilization procedures such as PGD and BTM. Because I do not explicitly discuss the role of women in relation to BTM, McLeod infers that I “ignore” their role in BTM. I am sympathetic to McLeod’s motivation to ensure that women are not being regarded as “mere vessels that do not deserve independent moral consideration” (McLeod 2005, 26). Academic writings of the past are replete with examples in which women are explicitly treated in this manner, and these writings are to be deplored. But it is a mistake to accuse an author of such an act simply because he or she does not explicitly discuss the role of women in relation to these procedures.

Françoise Baylis defines “non-viable” embryos as “embryos with no potential for ongoing growth and development because of a genetic or metabolic disorder that would cause the embryo to die at the pre-implantation, fetal or immediate post-natal stages of development” (Baylis 2005, 17), and she argues that these embryos could be used for hESC research without ethical qualms. I am skeptical about her proposal because we can similarly define “non-viable adults” as persons who have lived for some time but are about to die as a result of a genetic disorder. It would not follow that it would be ethically permissible to use these individuals for research purposes. If so, and if embryos are presumed to be persons, why does the fact that the embryo is about to die as a result of genetic defects matter? Baylis needs to explain why there should be an asymmetry between non-viable embryos and “non-viable adults.”

John A. Robertson is not an embryoist. As he says, “embryos that are going to be discarded have no inherent rights or status that prevents them from being donated for ESC research or therapy” (Robertson 2005, 20). Given this, I understand his frustration that BTM does not immediately enable one to proceed with hESC research. But given that BTM explicitly addresses the embryoists’ concerns, it could also be the case that more individuals would be interested in supporting this kind of approach with the net effect that we are able to get to the clinical stage of hESC research faster.

Robertson raises several points in connection with BTM, such as the name. The reason for using BTM is because “blastocyst transfer” denotes when the embryo would be re-implanted. Robertson’s proposal of “blastocyst biopsy” or “blastocyst sampling” does not indicate when the re-implantation would take place, only when the embryo would be biopsied. Robertson also says that my example of embryo blastocyst bisection is different from BTM, which involves blastocyst biopsy, and that I therefore “offer little credible evidence” to support the possibility of BTM. No doubt the two procedures are different. The point of the example is that if an invasive procedure such as cutting the blastocyst in half does not result in increased incidences of birth defects or abnormal offspring, then it seems that taking much fewer cells from the inner cell mass should lower the risk of harming an embryo even more.

Robertson further states that I do not discuss a similar method advanced by the President’s Council, which is to remove a cell from a pre-blastocyst stage. I actually discuss this method in footnote 15. One objection this method faces is that the cell extracted could still retain the potential to form a viable embryo, as it is extracted between the 1–4 day stage. If so, the embryoist objection would not be circumvented. Because BTM removes cells at the 5–7 day stage, when the cells have become pluripotent, this concern does not arise.

Moreover, Robertson says that “the 1500 or so births of children after [pre-implantation genetic testing] PGD are not sufficient numbers to establish that PGD has no effect on the well-being of the resulting children,” (Robertson 2005, 19) thereby implying that the risk involved in procedures such as PGD and BTM may not be ethically acceptable. In his writings, Robertson explicitly endorses the ethical acceptability of PGD (Robertson 2003). Therefore, I do not know what to make of his scepticism here. In any case, while the research regarding the longitudinal effects of PGD is ongoing, as far as I am aware there is no known specific pattern of birth defects resulting from PGD (Strom et al. 2000).

Finally, Robertson says that the “analogy of saving umbilical cord blood to benefit the child is inapposite because collecting cord blood involves no risk to the child” (Robertson 2005, 19). But it is not true that collecting cord blood involves no risk to the child. This procedure requires the clamping of the placenta, which can seriously injure the newborn, e.g. cause brain damage. My claim is again that the risk involved in BTM should be comparable to such risks.

In my article, I considered the worry that to develop BTM, one would have to harm some embryos initially, and I outlined a research process that addresses this worry which involves, among other things, examining an embryo’s family history for relevant diseases and using PGD to ascertain that the embryo has such a disease. Carson Strong questions this research process on several grounds. First, Strong argues that many of the diseases for which stem cell therapy is anticipated, such as cardiac ischemia, diabetes and Parkinson’s disease, would be ruled out on my approach, because “they are multifactorial rather than purely genetic and are not diagnosable by PGD” (Strong 2005, 21). This conclusion does not follow. PGD may still be able to offer some indication that an individual may develop a particular multifactorial disease on account of the fact that an individual has a certain set of susceptible genes. More importantly, I do not claim that PGD is necessary for ascertaining whether an embryo has a disease. Sometimes the family history may be sufficient to determine that the embryo is susceptible to a particular disease, e.g., if the previous five generations all had cardiac ischemia. Hence, a disease would not be ruled out using my approach just because it might not be diagnosable by PGD.

Secondly, Strong argues that my argument “depends on it being reasonable to expect stem cell therapy to be developed in time to help the preembryo in question” (Strong 2005, 21), but it is not clear that effective stem cell therapy would be developed in time to help that person. If so, one could not claim, as I have done, that there would be benefit to the research subject. Strong is assuming that the only type of stem cell therapy is embryonic stem cell therapy, but there are other types of stem cell therapies using adult stem cells or cord blood stem cells. We can use these other types of stem cells to ascertain whether stem cell therapy would be effective for a particular disease. If there is some success, we might then seek to use embryonic stem cells, assuming that we would achieve even more success. This would directly benefit those embryos involved in BTM.

Thirdly, Strong claims that my argument involves “selecting diseased preembryos for transfer” and one can object to this “on the grounds that it fails to treat the child as an end in herself.” Strong explains that one could raise such an objection, because “intentionally creating a child who is likely to have a significant disease-related impairment threatens the child’s ability later to choose and pursue her own ends” (Strong 2005, 22). However, selecting diseased preembryos for implantation is not the same as “intentionally creating a child who is likely to have a significant disease-related impairment” (Strong 2005, 22). I certainly agree that there is something wrong with intentionally creating a diseased individual (Liao 2005a), but in selection the diseased embryo is already created as a result of unfortunate circumstances. No one needs to have “intentionally” caused this embryo to have the diseased impairment. In deciding to implant this diseased embryo, an embryoist is deciding that the life of a person is more important than the disease impairment that the embryo may have. So, the embryoist does treat this embryo as an end.

Strong goes on to say that, “when there is a choice between a diseased preembryo and one whose health status is unknown, these considerations include deontological as well as consequentialist concerns” (Strong 2005, 22). This changes the topic, however. Whether a diseased embryo should be implanted is a different issue from how one should decide between a diseased embryo and one whose health status is unknown, which may involve, among other things, questions about resource allocation. The embryoist’s point is that if a child with a serious disease should be permitted to live, and if an embryo has a serious disease but is also a person, it seems that it should also be permitted to live.

Finally, Strong argues that “the mere fact that it is possible that research would advance more rapidly in the long run” (Strong 2005, 22) under BTM is not a convincing argument that research that destroys preembryos should halt. My point is not meant to be a knock-down argument against non-embryoists. It is meant to be a pragmatic invitation for embryoists and non-embryoists to come together to move the hESC research forward.

In my article, I also argued that other alternative proposals such as using parthenogenetic embryos, “dead” embryos and “pseudo-embryos” are unlikely to persuade an embryoist, because an embryoist might regard these embryos as persons who need special assistance. David Wasserman proposes that a similar claim could be made about the pluripotent cells I have proposed to harvest from 5–7 day-old embryos. In particular, Wasserman writes, “while these [pluripotent] cells cannot at present develop into human beings, there may soon be ways of restoring that potential lost just days earlier. If extracted stem cells could be made totipotent, those cells, like the entities subjected to an “improved” process of parthenogenesis, revived “dead” embryos, and pseudo-embryos that had their gestational genes turned on, would all qualify as live embryos and would be, for the embryoist, persons” (Wasserman 2005, 23).

However, there is an important difference between these quasi-embryos and the pluripotent stem cells. The pluripotent stem cells have lost their genetic basis for personhood in that some of the relevant genes for personhood are turned off, whereas the quasi-embryos may not have. We know that the pluripotent stem cells have lost this genetic basis because unless some of these genes are turned back on, these pluripotent stem cells cannot create full human beings. In contrast, there are reasons to believe that the genetic basis for personhood is still present in quasi-embryos. For example, it should be present in the “dead” embryos, since we are supposing that these embryos are like other embryos in all respects except for the fact that the cells in the “dead” embryos have stopped dividing. At least for those “dead” embryos that could be jump started again, this means that the genetic basis for personhood in the “dead” embryos should still be intact. A reason for believing that parthenogenetic embryos may have the genetic basis for personhood is that, in lower animals, parthenogenesis can create full animals without further genetic modification. Hence, in the case of human beings, the genetic basis for personhood is probably there but something else is preventing the parthenogenetic embryo from developing into a full human being. Finally, it is unlikely that the removal of the gene for the development of the placenta, as in the case of pseudo-embryos, is equivalent to the removal of the gene for personhood. The placenta is not present in marsupials or birds, yet these animals develop into their kind nevertheless. It is conceivable that a human embryo could be nourished in a different way than via a placenta. If so, we can infer that such pseudo-embryos have retained their genes for personhood and would therefore qualify as persons.

Wasserman (2005) suggests that my response might be grounded in a notion of “natural process,” and he questions this notion, especially as it applies to laboratory-manufactured quasi-embryos. Wasserman is contrasting the notion of “natural process” with “man-made” process. Another way to understand the notion of natural process is to see it as something like “inherent capacity.” A functioning embryo, whether man-made or not, has the inherent capacity to become a full human being, whereas a functioning pluripotent cell, whether man-made or not, does not have this inherent capacity.

Berry (2005) identifies three kinds of bioethics: reactive bioethics, proactive bioethics, and what she calls “bioethics as co-PI,” and she argues that my article belongs to the third kind. According to Berry, bioethics as co-PI seeks to arrive at bioethical solutions that, akin to Rawls’s Political Liberalism, could be acceptable to people with different worldviews (Berry 2005, 31). Berry believes that bioethics as co-PI plays an important role in the field, but she also cautions that it could be subject to two kinds of worries. First, in seeking to accommodate different worldviews, bioethics as co-PI could lack a “normative anchor” and could therefore threaten “to drift into an exercise in pure politics” (Berry 2005, 31). Secondly, if bioethics as co-PI did not have a normative anchor, it could be used by “an ideology” seeking to distort or deny rather than to acknowledge true science and true ethical commitments (Berry 2005, 32).

Berry is correct that my aim in this paper is to provide a compromise solution to hESC research for people with very different views about the moral status of the embryo. So, the article fits her description of bioethics as co-PI. But I think that her worries regarding bioethics as co-PI need not apply in this case. In providing a compromise solution to the hESC research debate, I am claiming that the hESC research can move forward without settling the debate regarding the moral status of the embryo here and now. But I do not claim that there is no correct answer regarding the moral status of the embryo, nor that we should not try to resolve this matter using sound philosophical argument. In fact, elsewhere I have explicitly discussed this issue (Liao 2005c). Moreover, neither the embryoists nor the non-embryoists can claim that BTM resolves the issue of the moral status of the embryo in their favor, because it does not aim to resolve this issue at all. As such, it cannot be used by an ideology seeking to distort or deny true science and true ethical commitments.