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A potential cure for Parkinson's disease has come a step closer with a British study showing it is possible to treat the degenerative brain disorder with cells derived from cloned embryos - a development the Vatican condemns.
The research was done on laboratory mice but scientists believe the findings are proof that the techniques could be applied to humans suffering not just from Parkinson's, but a range of incurable diseases.
Researchers have demonstrated the possibility of treating Parkinson's disease by transplanting laboratory-matured brain cells back into the individual who supplied the skin cells that were turned into cloned embryos - a process known as therapeutic cloning.
"This is an exciting development, as for the first time it may be possible to create a person's own embryonic stem cells to potentially treat Parkinson's disease," said Kieran Breen, the director of research at the Parkinson's Disease Society - a charity representing the 120,000 people in Britain affected by the illness.
Dr Breen said: "Stem cell therapy offers great hope for repairing the brain. It may ultimately offer a cure, allowing people to lead a life that is free from the symptoms of Parkinson's disease."
Proof that therapeutic cloning is more than a pipedream will be used by British scientists as justification for their push to expand the boundaries of their research to include the use of animal-human hybrid embryos for medical experiments, a process that is bitterly opposed by the Catholic Church.
Scientists say that, because of the shortage of human eggs for research purposes, they need to use cow or rabbit eggs for cloning experiments, and have lobbied hard for it to be allowed under the Human Fertilisation and Embryology Bill now going through Parliament.
Even though the stem cells derived from cloned hybrid embryos will never be used on patients, the practice is condemned by the church, which wants all MPs to be given a free vote in the House of Commons. The latest development, published in the journal Nature Medicine, is further proof-of-principle that therapeutic cloning can effectively treat - and possibly cure - a degenerative brain disorder.
For the first time, scientists have been able to create healthy, working brain cells from immature stem cells, derived from embryos cloned from skin cells, and transplant them back into the diseased brain.
The laboratory mice in the study suffered from a type of Parkinson's disease, which is marked by the death of certain nerve cells or neurons in the brain that produce the neurotransmitter dopamine.
Skin cells were scraped from the tails of the animals and cloned using mouse eggs.
Stem cells taken from the resulting cloned embryos were grown into mature dopamine-producing brain cells. The treated mice showed improvements.
- INDEPENDEN