Copyright 2004 Times Newspapers Limited  
The Times (London)
February 19, 2004, Thursday
SECTION: Home news; 12
630 words
BYLINE: Nigel Hawkes

The aim is an understanding of motor neurone disease, writes Nigel Hawkes

The team that cloned Dolly the sheep plans to move into human cloning.

Ian Wilmut, leader of the team at the Roslin Institute, near Edinburgh, says that it will be applying for a licence to clone stem cells from patients with motor neurone disease.

The first aim, he writes in New Scientist, will be to understand the disease better by studying what goes wrong in the nerve cells in the brain and spine to cause it. He adds that human cloning will have benefits first in understanding and only later in treatment.

The disease the team plans to study is ALS (Amyotrophic Lateral Sclerosis), known in America as Lou Gehrig's disease, after a baseball player who died from it.

Stephen Hawking has suffered from ALS all his adult life, but his disease has progressed much more slowly than usual. ALS normally kills within five years of diagnosis. About 10 per cent of cases are inherited, but the rest arise spontaneously for reasons that are not understood.

Studying ALS is difficult because the motor neurones affected cannot be removed for examination. "Using cloning to create cultures of motor neurones from such patients would help us to track down the causes of the disease," Dr Wilmut says.

"What damages these cells? Does the damage come from within, or from faulty interactions with other cells?

"What is more, being able to study which genes are switched on or off in such cells could tell us which might be going wrong in the 90 per cent of ALS patients who did not inherit their condition. Cloning might even give us the chance to test new therapies."

The procedure will take a cell from an ALS patient who has inherited the disease and use it to clone that patient by inserting it into a human egg from which the nucleus has been removed. The egg will then form an embryo which will be allowed to grow for about a week, before cells are taken and grown in cell culture to produce embryonic stem cells. From these, given the right conditions, motor neurone cells could be produced for study.

Because these cells would incorporate the genetic flaw responsible for the disease, studying the genes might give clues about how it developed, not only in inherited cases but also in the other 90 per cent.

The technique might also be used for studying Parkinson's and Alzheimer's disease, Dr Wilmut says.

Many people object to cloning research because they fear it will open the door to producing cloned babies, he says, or because they think that experimenting with human embryos is immoral.

He argues the opposite. "Cloning promises such great benefits that it would be immoral not to do it." For example, cloned cells might be used to test new drugs.

Bad reactions to drugs, even those prescribed correctly, cause thousands of deaths every year. By cloning liver cells from families who had suffered bad reactions, the gene activity could be studied and variations identified, ultimately leading to better tests for drugs.

Finally, he says, cloning might be used to treat inherited diseases. Parents can try to avoid passing on such diseases by having IVF treatment and screening the embryos for the genetic flaws. But if no undamaged embryos are found, they face a second round of IVF.

A way round this might be to take stem cells from an IVF embryo, correct the defect by genetic engineering and then use the corrected cells to create a clone, using another egg.

"The resulting embryo would be the identical twin of the original one, but with the diseased gene corrected in every one of its cells," Dr Wilmut says. "Although such a child would be a clone, it would be the clone of a new individual, not the clone of one of its parents."