An EU Council of Ministers' vote later this month on embryo research willonce again concern and confuse the public. Dick Ahlstrom, Science Editor, explains the issues
Brace yourselves for a fresh round of claim and counter-claim about the good or evil arising from proposed research into the human embryo. The Tánaiste travels to Brussels later this month to vote on whether EU funding - using community taxpayers' money - should pay for the research.
The battle lines and main combatants are already familiar to the Irish electorate, having been seen and heard during earlier conflicts about abortion and any debate touching on embryos. Be prepared too for the leafleting as the two sides of the argument crank up their information campaigns in search of support.
Already Youth Defence has begun characterising the research proposal as nothing short of experimentation on human beings. Many in the scientific and medical community take a more moderate view, arguing that embryo research might lead to cures for degenerative diseases of the mind and body.
The technicalities surrounding the vote on November 27th are simple enough. The EU agreed its €16 billion research budget in December last year but caused major controversy because it included funding for embryo research. Such was the disagreement that a moratorium was imposed on cash for this work, allowing the rest of the budget to go ahead.
In July the commission issued compromise proposals to lift the moratorium next month. The European Parliament's legal affairs committee rejected the compromise, but its industry committee this week voted to support the commission view. The parliament will vote through an "opinion" on the issue on November 18th, then the Council of Ministers (formally known as the Council of the European Union) must decide either to lift or maintain the embargo.
The parliamentary procedures are straightforward, but finding an answer that does not cause ethical controversy and upset is a far greater challenge. The difficulties are inescapable given that the issue involves the weightiest of ethical considerations: what is life and when does it begin?
The issue is not about the creation or handling of human embryos, because we do that all of the time already, almost as a matter of routine. Millions of couples would be childless were it not for in vitro fertilisation (IVF) and the creation of embryos for implantation in the womb. Only a small minority of people continue to reject this valuable medical practice, a procedure that helps to produce healthy children.
The "what is life and when does it begin" questions creep in soon afterwards, however, after couples have benefited from IVF treatment. It is normal to produce so-called supernumerary embryos, extras to be used if something goes wrong. The embryo research the European Commission wants to fund with your tax euro involves using these supernumerary embryos.
There are two main answers to the question of when life begins: at the moment of conception (when egg and sperm fuse) or some time later. If you accept the first, then any embryo, even supernumerary frozen ones, represent human life and merit protection. Those seeking to block the research proposal will argue that the research destroys life. Those in support of embryo research tend to hold the view that life begins later.
Which side is correct? This is the big ethical question everyone must answer for themselves.
The Catholic Church's traditional view is that it begins at conception; this is the spur that drives Youth Defence to protect the embryo. The secular view, however, and that held by the Government when drafting legislation associated with the third constitutional referendum on abortion, is that life begins when the embryo implants itself in the womb, two to three weeks after fertilisation.
But why does the research have to use embryos? The experiments will use them as a source of stem cells. An embryo contains only a tiny collection of cells, but from these few grow the 200 or so tissue types found in the adult body.
Stem cells are the source of all this variety, and researchers are quickly learning how the growing fetus manages to change an undifferentiated stem cell into liver, bone, skin and muscle through the controlling action of genes.
The current hope is that stem cells could be used to help repair a severed spinal cord, rebuild heart muscle or counter the effects of Parkinson's disease and diabetes. Experiments on rats and mice have shown that stem cells can reverse some types of damage.
The intractable problem is that the embryo is destroyed when the stem cells are harvested. And this brings us back to the ethical crux associated with this research.
There are other sources of stem cells. The adult body produces small numbers of replacement stem cells, and these too hold promise in medical treatments. They are difficult to recover compared with those in an embryo, and, most importantly, they are nowhere near as plastic, or versatile, as those from an embryo.
Stem cells are also available from the placenta and umbilical cord, but these behave more like adult stem cells than embryonic stem cells. Their value is being studied in labs around the world.
Researchers have also managed to culture embryonic stem cells, producing a perpetual supply of cells grown in flasks. They appear to perform much like those from an embryo, but the research area is so new that it is difficult to know if they are actually the same.
Another ethically contentious approach is to try to clone embryos. The EU research would involve only supernumerary IVF embryos frozen before June last year.
Cloning would provide an endless supply of embryos and stem cells. Research on this is under way in the UK, the US and elsewhere, but it makes most people very uncomfortable. Researchers believe the technique could be used to produce source material for replacement tissues and even whole organs grown from a person's own DNA, providing a perfect match for transplantation.
Editorial comment: page 19
Stem cells These are the source cells from which the body's specialised tissues grow. They change from an unspecific, undifferentiated state into a differentiated "adult" state, taking on one of the body's more than 200 cell types.
Embryonic stem cells These are the most plastic, or changeable, stem cells, apparently able to differentiate into any of the body's tissues. Their use is controversial because they are recovered from a dividing embryo, but their plasticity means they may be the most valuable form of stem cell for medical treatments.
Adult stem cells Adults also produce stem cells, but they are much less changeable
than embryonic cells. They have been
found in liver, marrow and brain tissue and tend to turn into cells appropriate to these locations.
Umbilical and placental stem cells Stem cells have also been recovered from the placenta and umbilical cord, although they act more like adult stem cells than embryonic ones. Their value is still being assessed.
Stem cell lines These are cultured stem cells originally taken from embryos but which now divide perpetually. Many countries accept research using cultured stem cells, including Germany, which has legislated against embryo research.
Embryonic cloning Being able to clone embryos, an ethically fraught notion, would produce an endless supply of embryos and an endless supply of stem cells.