As peers threaten to block government plans to allow the cloning of embryos, science editor Tim Radford looks at a medical revolution
Special report: the ethics of genetics
Monday January 22, 2001
DNA has been around for 3.8bn years, renewing itself with each life at conception. In humans, a length of adult DNA from a male enters an egg and unites with DNA from a female, turns back the clock, becomes the first infant cell, divides and starts a cascade of reactions that turns one fertilised egg into 1,000bn cells of more than 200 different kinds.
How it does this is a whole series of mysteries, but one key to these lies in first stem cells from which all bone, skin, blood and nerves subsequently stem. These appear in the first 14 days, before the cell implants in the womb.
For the last 10 years, British scientists have used embryos up to 14 days old to assist infertile couples to a pregnancy, and to study the puzzles of infertility.
Four years ago, Scottish scientists stunned the world by taking DNA from a dead sheep and growing Dolly. Then three years ago, US scientists working with private money managed to "immortalise" stem cells in a laboratory dish.
The combination of the two discoveries seemed to open a magic door: onto a horizon in which incurable, irreversible diseases such as multiple sclerosis and Parkinson's disease could be one day cured. "Personalised" stem cells could be grown in a dish, and implanted in a sufferer, to make new nerve cells grow. The paralysed Superman actor, Christopher Reeve, might walk again.
American federal law will not permit taxpayers' money to finance embryo research of any kind, but US private laboratories can do what they like.
In Britain, all such research is subject to the Human Fertilisation and Embryology Act. A government committee considered the opening, and gave the green light to a very limited extension to permit research into embryos up to 14 days old for other diseases besides those of infertility.
Nervously, the government created another committee, which also gave the green light. Again nervously, the government then permitted a free vote in the House of Commons. It passed, by a huge majority.
Now, driven by some, but not all, religious groups, the House of Lords could kick the legislation into touch, or at least into the next parliament, by referring "therapeutic cloning" to a committee.
Dissidents argue that latest experiments with "adult" stem cells mean that embryos may need never to be used. There is a case: there could never be enough donated eggs to make the stem cells that doctors would ultimately need.
The hope is that ultimately stem cells from adults could be "reprogrammed" to cure diseases. But at present, the only way to get to that point is to study stem cells as they emerge in the first 14 days, using surplus embryos that would otherwise be destroyed.
The Roman Catholic church and other groups talk of embryo stem cell research as a "dehumanising" and disastrous step. That's not how Parkinson's disease and muscular dystrophy campaign groups see it, nor the British Medical Association, nor the Imperial Cancer Research Fund, nor Diabetes UK.
The issue explained
30.08.2000, comment by Tim Radford: Why not clone a human?
16.12.2000, leader: Stem cells offer hope
House of Lords
Human Cloning Foundation
religioustolerance.org: Ethics and cloning