The Daily Telegraph today reports on its front page (and now being picked up by various others) that Professor Ian Wilmut, the scientist behind Dolly, the cloned sheep, has abandoned the cloning method (nuclear transfer) which he developed to explore an alternative approach pioneered recently in Japan by Professor Shinya Yamanaka and apparently replicated in the US. The crucial ethical issue here is that this alternative does not require the creation and destruction of embryos as pluripotent stem cells are gained from manipulation of adult stem cells.
The Telegraph reports
Prof Wilmut is backing direct reprogramming or "de-differentiation", the embryo free route pursued by Prof Yamanaka, which he finds "100 times more interesting."
"The odds are that by the time we make nuclear transfer work in humans, direct reprogramming will work too.
I am anticipating that before too long we will be able to use the Yamanaka approach to achieve the same, without making human embryos. I have no doubt that in the long term, direct reprogramming will be more productive, though we can’t be sure exactly when, next year or five years into the future."
Prof Yamanaka’s work suggests the dream of converting adult cells into those that can grow into many different types can be realised remarkably easily.
While there must always be caution about these claims (other approaches not using human embryos have been heralded in the past) and the Yamanaka alternative may well raise ethical dilemmas of its own, this looks a most exciting development.
For those wanting a short (133pp), accessible and inexpensive (£3.99) introduction to the whole debate a good recent guide is Ted Peters’ The Stem Cell Debate
It is a guide to the debate by a Christian theologian who has been very involved with scientists working in this area. He is a strong defender of human embryonic stem cell research due to the benefits it is likely to bring in terms of relieving suffering. The book provides a really helpful guide to the science and then sketches three different frameworks for ethical responses - embryo protection, nature protection and medical benefits - which he argues are incompatible and which explain why the public debate leads to so much conflict. A fourth framework sets research standards (eg protection of embryo after 14 days). The final chapters spell out more of his theology of humanity (to explain why he does not see the early embryo as an inviolable human person). I’m not convinced by his treating the frameworks as incompatible nor by his positive assessment of embryonic stem cell research based on his preference for the ’medical benefits’ framework. In addition, if I understand the Telegraph report correctly, his crucial and negative discussion (pp38-9) of ’could adult stem cells provide pluripotency?’ may be being overtaken by latest research. Despite these significant weaknesses, this is a helpful guide to the debate and the issues.
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