Madam, - In such a vital consideration as the use of stem cells in disease processes, it seems that many people are confused about the fundamental difference between human embryonic and adult stem cells.
Human embryonic stem cells were first cultured in the United States in 1998 but, as yet, have had no clinical application, largely because of doubts about their efficacy and safety in animal models.
On the other hand, adult stem cells, derived from such diverse tissue as mucous membrane, muscle, bone marrow, umbilical tissue and umbilical cord blood, have been quite effective and safe when used in the human subject.
For example, stem cells derived from the patients' bone marrow have brought about heart muscle regeneration in hearts damaged by coronary artery disease and chronic ischaemic heart disease. The achievements of a team at the Heinrich-Heine University of Dusseldorf are well authenticated.
At the same time a group of medical scientists at the Medical College of Georgia in the United States have reported the use of stem cells derived from bone marrow and umbilical cords in bringing about neurological repair, especially following stroke injury, while very promising results have been reported from Newcastle-upon-Tyne using stem cells derived from umbilical cord blood.
At home, exciting research on umbilical cord blood stem-cells which, hopefully, will shortly lead to clinical application, is being conducted by a team of medical research workers at the Regenerative Medicine Institute of NUI Galway.
Why is it, then, that successful use of adult stem cells has been totally ignored by the media, while embryonic stem cells are hailed as the panacea for a variety of medical disorders?
The production of embryonic stem cells involves the killing of a human embryo. To those who believe that human life, like other mammalian life, begins at fertilisation, the deliberate destruction of a human embryo - for whatever reason - is anathema. Research necessitating the killing of a human embryo is rightly considered an affront to human dignity. Should such research not be prohibited through legislation?
Apart from consent, no ethical problems arise with adult stem cells. Hence, the State should be encouraged to invest in research into adult stem cells and their clinical application.
- Yours, etc,
EAMON O'DWYER, Professor Emeritus of Obstetrics and Gynaecology, NUI, Galway.