A French doctor speaking to the press after the world's first transplant of foetal cells into patients with Huntington's disease.

PARIS (AFP) - French researchers have said that gene therapy, tested on lab animals, showed promise in combatting the tragic neurogenerative disease known as Huntington's.

The disease strikes around one person in 10,000, with the problems mainly showing up between the early 30s and the age of 50.Its symptoms are uncontrolled, jerky movement, leading to personality change, dementia and death, which occurs between 10 and 20 years after the first signs emerge.Huntington's is caused by a flaw in a single gene on Chromosome 4 called IT15. It causes a mutated form of a protein called huntingtin to run riot, killing cells in the striatum region of the brain.Scientists at the Institute of Biomedical Imaging and Molecular Imaging Research Centre, part of France's Atomic Energy Commission (CEA), said they were experimenting with a modified virus to deliver a corrective gene into brain cells that boosts a natural shield against Huntington's effects.The neuroprotective molecule is called ciliary neurotrophic factor, or CNTF."When the brain has a problem or a lesion, then the synthesis of CNTF is increased," and helps neurons to survive, said researcher Nicole Deglon, in a press release.Like a Trojan horse, the virus is injected into the striatum, where it infects brain cells, inserting the gene for CNTF.Experiments on lab rats, followed by primates, show that the technique does protect striatum cells, and the team is now moving towards a clinical trial on humans, the press release said."Our hope is that the patient will benefit for several years, but the answer will be the clinical data," said Deglon.Their research was unveiled on Tuesday at a five-day conference in Geneva, organised by the Federation of European Neuroscience Societies (FENS).Similar work in this field is being carried out by US researchers at Rush University Medical Centre, Chicago, using a defective cold virus to deliver a different gene, called glial-derived neurotrophic factor (GDNF), into mice brains.GDNF controls a protein that protects brain cells that are at threat from Huntington's.Gene therapy is one of the most exciting areas of medical research, as it offers the tantalising prospect of being able to slow, stop or even reverse a disease by correcting a flawed gene.However, enthusiasm has also been dampened by several bad setbacks when experiments that did well on lab animals backfired when tested on humans.Clinical trials are long because they are hedged with conditions and periodic reviews to ensure the prototype treatment is safe.Meanwhile, in the latest issue of the Journal of Experimental Medicine, British researchers said they had found that an inflammation-causing protein called IL-6 could serve as an early warning sign of Huntington's.People with high levels of this protein went on to develop symptoms of the disease more than a decade later.