One of the big problems with maturing regenerative medicine into a clinical therapies is the difficulty with obtaining stem cells that are sufficiently pluripotent - that is that they can form any variety of descendent cells required and can fully integrate into the hosts body without rejection.
Stem cells can be obtained from adults or umbilical cord blood etc. and although therapies generated from these types of stem cell are entering clinical trials ahead of embryonically derived cells at the end of the day their usage will be limited as they are already way down the stem cell pluripotency line and can only form limited cell types.
Hence the great interest scientists have in stem cells derived from embryonic sources as these cells have maximum viability and flexibility in terms of potential treatment use. Many Christians have big ethical problems with using embryonic cells as it does mean the creation and disassembling of the embryo involved.
Whilst I do not personally share these concerns (due to a number of reasons both scientific and theological) I am pleased to see some good progress being made on the creation of an alternative method of deriving embryonic-like stem cells by groups in here in Edinburgh. Although there is still work to be done this is clearly a big step forward. It will provide more tools in the stem cell tool kit and increase our understanding of the underlying mechanisms involved which will bring wider benefits to stem cell therapies derived from the other sources as well.
This method would also initially appear to have less ethical problems than the existing methods of creating embryonic stem cells and indeed many conservative bioethics groups have been saying this for a while now.
It does however pose a new question for those reluctant to use embryonically derived cells. Much of their reasoning relies on proposing that the embryo has the quality of personhood due to its biological potential to become a human being. A potential human being here is protected with the full rights of a realised human being.
With this new method of producing embryonic-like stem cells, does there come a point however where we drop the semantics of 'like' and regard these created stem cells equally as potential human beings? Physically the difference between embryonic stem cells derived from the two methods would ideally be minimal to non-existent so any difference might end up boiling down purely to using a language of convinience to make us more comfortable with one method rather than the other.
If so then this new method is no more or less ethical than before, but if not do we then have to factor into account the method of production in our ethical deliberations even if the physical output is the same? If so what do we define as the method of production that endows potential personhood? If it is the creation of an embryo via the combination of sperm and egg that we would choose since it is the 'natural' method of production, can we continue to call into question the ethics of creating embryos ex vivo in the lab as scientists currently do to obtain embryonic stem cells?
It strikes me that this could fast become another case of 'angels on a pinhead' and that if objections to the use of embryos for generating stem cells are to continue then it may have to be a case of all or nothing rather than picking and choosing between methods we see as more emotive or mechanistic.
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I think you've misunderstood or misrepresented the position of many who are opposed to using cells from embryos.
"Much of their reasoning relies on proposing that the embryo has the quality of personhood due to its biological potential to become a human being. A potential human being here is protected with the full rights of a realised human being."
I'm sure this applies to some opponents, but according to a Catholic understanding (and no doubt many others), this misses the point.
The Catholic understanding is that from conception there is human life, not "potential human" life.
It is true that the Church often says such things as "[The embryo] must be treated from conception as a person", but that doesn't mean to say that the existence of a person isn't recognised, merely that their human rights are emphasised as being equal to those who have already been born.
"Human life must be respected and protected absolutely from the moment of conception." CCC 2270
I'm certainly no authority on the matter, but to me it seems likely that the Church wouldn't see the addition of four genes to skin cells (obviously from a person who is in no way harmed by the process) as equivalent to conception from the genetic material of two adults.
The cells produced by this method - would they, in the proper environment, develop into a child? (Just so I don't sound entirely ignorant, I imagine that's not the case)
If not, I don't suppose it's any more like abortion than organ donation is.
Also, I'm interested in finding out what your scientific and theological reasons for not being concerned about the issue are.
I wouldn't say I have misrepresented the Catholic position given how (my understanding anyway) it is that the fertilised egg has the potential for ensoulment by God at a time of his choosing and that is what gives the fertilised egg its personhood status. Thus it is not a full human but rather a potential human until God embodies it with a soul. This is a process that is admitted is unquantifiable by measurement of the embryos physical substance. Scientifically there is no 'moment' of conception anyway.
The addition of the genes here reprograms the adult cells into a pluripotent embryonic form with the objective of making them as physically similar to prior methods of obtaining embryonic stem cells.
In the proper environment it is conceivable they could develop beyond their pluripotent stage and start to differentiate into later stage tissues if not into a full child. As is the case with all embryonic stem cells.
I think this new method of deriving stem cells is quite exciting and has significant advantages to others but is perhaps just as ethically challenging.
(For my own views on these matters I would say they are broadly consistant with (amongst others) those of John Bryant (a cell biology professor at Exeter with an interest in bioethics) and those of Ted Peters (a theologian from the US) who have both written some excellent books on these sorts of topics.)
I still think you've got the wrong end of the stick with regard to the Catholic position. Put simply, the Catechism, which is probably the most convenient summary of the Church's teaching at this time, says that "[h]uman life must be respected and protected absolutely from the moment of conception."
If human life doesn't exist at the moment of conception, then the above is really meaningless; it can neither be protected nor respected.
Whether or not the Catholic position can include your view of what it means as well, I'm not sure, but I think that for many this issue of ensoulment is a non-starter, because they believe that life, and personhood, begins at conception.
What does it mean to say that scientifically there is no moment of conception?
Do I really have to buy a book to find out what you think? I'd appreciate an idea at least.
Whether or not I have the wrong end of the stick or not with Catholic teaching the outcome of that thinking is still the same for Catholics and others who hold that the use of embryos for the generation of therapeutic treatments - that it is immoral.
I'd rather you bought one of the books (especially Bryants) as they explain things a lot more clearly and over more space than I can.
When I say there is no moment of conception I mean that there is no 'magical' moment when the egg is fertilised. It takes time for the sperm to penetrate the egg, more time and then more time for the new genome to form and then further time for chemical signalling to begin reproduction to start.
My position is that a unique genome is insufficient for personhood (think twin, chimeras etc) and that develops after implantation when the fertilised egg can no longer be flushed out by the mothers body and the first distinct individual structures begin to develop.
This is also the very earliest the mother can become aware she is pregnant. And since there is incredible interplay between the mother and the developing embryo this is pretty important.
Interestingly this is still before the 40 days that is generally considered the start of a new life from Jewish traditions.
Hi,
I think that
it is important to delineate the respective positions. If we're talking about potential human beings that's ethically troubling. If we're talking about human beings, murder is the right word. There's quite a wide range within the word "immoral".
To say that there is no 'magical' moment of conception doesn't strike me as very important. The "moment" of conception can be understood as the beginning of the process, or perhaps the end. By selecting implantation as the 'magical' moment of the beginning of the process of personhood, you're proceeding to answer a philosophical and theological question with a scientific method; strictly speaking, an impossibility, though obviously science can and does aid philosophical and theological enquiry.
With regard to the fertilised egg not being able to be "flushed out", I believe that a baby can be rejected by the mother's body very late term, resulting in a miscarriage or stillbirth. If this were the case, that would make the criterion irrelevant. Moreover, that people die before they are implanted in the womb is no more philosophically unacceptable than that people die at any other stage. Also, I should think that a genome is a distinct individual structure. If so, it doesn't make sense to choose the structures to which you refer in preference to the genome. Neither can the mother's awareness of the pregnancy answer the question. A soul is never demonstrable from scientific observation - the mother's feelings can hardly be a more valid test. Besides, there has already been incredible interplay between the mother and the embryo in conception, where the embryo receives half of its genetic information from her.
I understand that we are currently unaware of what causes the embryonic fission that results in identical twins. This being the case, it may be that the fission is inevitable from genetic or environmental factors. In this case, it wouldn't be unreasonable to assume that there were two souls from the beginning. Or it is possible that there is only one soul at the beginning which becomes two. I gather you don't accept this idea, but I don't see that it's possible to reject the idea whilst maintaining at the same time that Jesus is "eternally begotten of the Father, [...] true God from true God, begotten, not made, of one Being with the Father"; He is of one being with the Father, yet is begotten, a distinct person.
Chimeras would be a separate mystery, but no more impossible than the full humanity and divinity of Christ, the procession of the Holy Spirit from the Father and the Son, the union of the Church as the body of Christ, and that man and wife are "no longer two, but one flesh".
That we don't know how it works can't be an insuperable obstacle. We may think "that a unique genome is insufficient for personhood" but we might also think that 5 loaves of bread and 2 fish were insufficient to feed more than 5,000 people, and yet they weren't. Of course, we know that the second is a miracle - it breaks all the usual rules, but in the case of souls and "personhood", we don't even know the rules unless God tells us.
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