AN INJECTION of genes to the brain could substantially reduce the symptoms of Parkinson’s disease, scientists at biotech firm Oxford BioMedica have discovered.

The treatment, ProSavin, improved walking and dexterity by up to 61 per cent in the nine patients in an initial safety trial, a conference was told.

Parkinson’s disease, which causes tremors and muscle stiffness, is caused by the death of brain cells that produce a chemical called dopamine which is essential for co-ordination.

The trials were on patients who had ceased to be helped by a drug called L-Dopa, which boosts dopamine but can cause muscle problems.

The jab contains three genes which produce enzymes that set up a replacement dopamine ‘factory’ in the brain.

The nine patients given the injection have seen an average reduction in shaking and stiffness of 43 per cent.

One patient saw a 61 per cent improvement.

There were no serious side-effects, the American Society of Gene and Cell Therapy’s conference heard.

Tom Isaacs, of The Cure Parkinson’s Trust, said: “ProSavin is one of the more advanced of the gene therapy products in development and is unique in its aim to achieve dopamine replacement. These results demonstrate it also has the potential to make a huge difference to those of us living with this terrible condition.”

Stuart Naylor, of Oxford BioMedica based at the Oxford Science Park, said the findings underlined the potential for the new approach.

More trials are planned but the drug is at least six years away from sale.