The technique will allow patients whose brains have degenerated to grow replacement cells for the damaged tissue. Patients with Parkinson's lack cells that release the chemical dopamine.
Dopamine carries messages around the brain.
The discovery could lead to doctors being able to offer unlimited supplies of dopamine-secreting neurons. The work involves stem cells, which are basic cells with no particular function. They can be cloned and grown in the laboratory. Doctors have been working on them because they hope the cells can be coaxed to take on the function of more specialised cells. The discovery, which was made in experiments using rats, comes less than a week after the government reject calls to let scientists clone tissue from embryos for such experiments.