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.