News that researchers in Japan and the US have successfully reprogrammed ordinary skin cells to become stem cells opens up huge opportunities for Irish scientists. It takes away a massive ethical burden by allowing researchers here to produce their own stem cells without having to destroy human embryos.
"What this means for Ireland is now we have an opportunity to become a world contender in stem cell research," said Dr Stephen Sullivan of the Harvard Stem Cell Institute in Boston.
"The need for human embryos for this research has been alleviated . . . and if Ireland wants to get involved in stem cell research, now is the time to do it."
Two teams working separately in Kyoto University in Japan and the University of Wisconsin-Madison in the US have achieved remarkable successes in producing growing lines of stem cells by reprogramming skin cells taken from a 36-year-old woman and a newborn infant.
The two groups used a virus to carry just four extra genes into the cells, causing them to "forget" they were skin cells and change into stem cells that are indistinguishable from the stem cells being harvested from growing human embryos.
Embryonic stem cells are like a kind of "starter" cell because they have the capacity to change into any of the body's 220 different cell types. Growing embryos use them to produce the brain, organs, muscle and bone.
These pluripotent cells are highly prized by medical researchers, who believe they can be used to deliver new medical treatments for conditions that are currently irreversible.
For example, stem cells introduced into the heart could be used to repair damage caused by heart attacks and if released in the brain could reverse the nerve damage seen in Parkinson's disease. None of these treatments has been proven yet, with work being held back because of the ethical complexities.
The huge ethical issue that built up around the destruction of embryos for this purpose has served to inhibit stem cell research.
In the US, president George W Bush blocked federal funding for certain embryonic stem cell research. Yet he welcomed yesterday's research announcement.
In an Irish context the Irish Medical Organisation's ethical guidelines prohibit any embryo research conducted by doctors registered with it, and biomedical scientists have not moved to become involved in studies involving embryos.
Yet extensive research is under way here on stem cells recovered from adult tissues at centres such as NUI Galway, University College Dublin and elsewhere. Adult stem cells can be harvested without any harm to the donor.
But now these ethical strictures have been lifted because pluripotent stem cells can be derived from a source other than embryos. With this new approach the "substantial ethical question would go away" stated the scientific director of the Irish Council for Bioethics, Dr Siobhán O'Sullivan.
This brings stem cell research using this technique within the reach of even moderately equipped biomedical labs, and without the ethical and legal constraints.
"They have all the capacity of embryonic stem cells without all the controversy," stated Dr Sullivan, whose lab confirmed the accuracy of the stem cell research findings. "It has been independently confirmed in our lab here and elsewhere in Boston," he said.
Both Dr Sullivan, who hails from Cork, and Dr O'Sullivan referred to limitations to the technique, as readily highlighted by the Japanese group led by Prof Shinya Yamanaka and the US group led by Prof James Thomson.
For example cancerous cells develop in as many as one in five cell lines. This was caused both by the virus used and the genes being delivered into the skin cells, said Dr Sullivan.
He believes however that this problem will readily be overcome. "This is just a technical problem that will be solved within two years," he stated.
Both of the lead scientists also said this new kind of stem cell would have to be studied carefully to ensure they really were a perfect match to embryo-derived stem cells.
For this reason Profs Yamanaka and Thomson argued that work on true embryonic stem cells must continue until their own approach can be proven to deliver.
"We are still a long way from finding cures or therapies from stem cells and we don't know what processes will be effective," Prof Yamanaka stated.
