The ethics of stem cells

Stem cells have been used in medicine for many years in the form of bone marrow transplants. More recently, the use of embryonic stem cells in therapies and research has lead to controversy and debates regarding the ethics of such use. The embryos used originally were donated from those left over after fertility treatment. More recently the law in the UK has changed so that embryos can be specifically created in the laboratory as a source of stem cells.

The removal of stem cells from embryos normally results in the destruction of the embryos, although techniques are being developed that will allow stem cells to be removed without damage to embryos. There are not only religious objections to the use of embryos in this way but moral objections roo - many people believe that life begins at conception and the destruction of embryos is, therefore, murder. There is a lack of consensus as to when the embryo itself has rights, and also who owns the genetic material that is being used for research.

This controversy is holding back progress that could lead to the successful treatment of many incurable diseases. The use of umbilical cord stem cells overcomes these issues to a large extent, but these cells are merely multipotent, not pluripotent like embryonic stem cells, rhus restricting their usefulness. Adult tissue stem cells can also be used but they do not divide as well as umbilical stem cells and are more likely to have acquired mutations. Developments are being made towards artificially transforming tissue stem cells into pluripotent cells. Induced pluripotent stem cells (iPSCs) are adult stem cells that have been genetically modified to act like embryonic stem cells and so are pluripotent. Of course the use of plant stem cells does not raise the same ethical issues as animal cells but they are not as useful for treatment and research and animal stem cells because they have largely different properties and cannot be used to treat diseases in the same way that animal stem cells can.

	Criado por Emily Rowland-Rawson quase 8 anos atrás

Notes for chapter 6, cell divisions, of the OCR A-level biology specification.