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Canadian scientists have pinpointed a possible trigger for Huntington's disease, saying that a viable treatment for the debilitating illness could now be less than a decade away.

The team led by Dr. Michael Hayden at the University of British Columbia yesterday made public the results of its 10-year project -- pinpointing one enzyme called caspase six that could cause the disease. "For the first time, we know what we want to target very specifically," Dr. Hayden said.

"We have a defined target we want to hit. This is a crucial step."

It has been a long, tough road from the "serendipitous" discovery, in 1996, that a key protein in the brain is sliced in several spots by molecular scissors, leading the researchers to hypothesize that it was this cleavage that led to Huntington's symptoms.

Most scientists believed the discovery was interesting yet of little use.

But Dr. Hayden, the director of the University of British Columbia's Centre for Molecular Medicine and Therapeutics, fought for funding to follow his instinct that it held greater possibilities.

Now the research is paying off. His team bred different families of mice that each had just one part of the protein being cut by the scissorlike enzymes.

All except one breed of mice developed Huntington's disease.

That meant the scientists had discovered the one link in a 10,344-ladder protein that may trigger the illness.

Dr. Hayden didn't believe it at first, and had lead researcher Dr. Rona Graham repeat the testing for about a year. It wasn't doubt of Dr. Graham's work that made him pause -- it was the massive impact of her findings.

"They were cured," Dr Hayden said of the mice. "When you prevent that cut, you don't get the disease. If we can do what we've done [with the mice]in humans, we've got a chance of treating the disease. We can try to knock out those scissors."

The research could have implications in treating other neurological diseases, such as Alzheimer's disease, but Dr. Hayden was cautious about being too optimistic.

"There's tons of work to do here," he noted. "We've got a lead, but we're not there yet."

Now completing his PhD with Dr. Hayden's team, Jeff Carroll is trying to translate the latest findings into a clinically viable treatment.

It's a personal quest: Mr. Carroll is one of the thousands of Canadians who carries the Huntington mutation, and he wants to see his soon-to-be-born twins grow up.

The twins themselves are safe because Mr. Carroll and his wife screened their IVF embryos to ensure the mutation wasn't passed on, but a cure could save Mr. Carroll from the disease that killed his grandmother earlier this year and is slowly claiming the life of his mother.

"Perhaps for the first time ever with a disease like this, we know exactly what we need to do to stop it," he said.

"If it's going to happen in my lifetime, it will. If not, I did everything I could."

Just the possibility of a treatment is thrilling news for families dealing with a disease, said Liz Manique. Her father, Alberto, was diagnosed with Huntington's disease 17 years ago, at the age of 41.

Mr. Manique was moved to a Toronto nursing home two months ago, after 10 years of full-time care at home.

"Once it's in your family, it's always in your future. It's really overwhelming. There's no getting away from it," Miss Manique said yesterday.

"Any good news is just so huge. If this doesn't work, it lets you believe they'll come up with something else."

While Huntington Society of Canada executive director Don Lamont said years of work still lie ahead, the possibility of early treatment was exciting for people now living with the disease.

"This takes that seed of hope and enables them to sustain the journey they have to endure," Mr. Lamont said.

Just as important, the breakthrough could bring essential investment dollars to support the continuing research.

Huntington's disease is an inherited brain disorder that affects neurons in one small hub in the brain, causing physical, emotional and mental deterioration.

One in 10,000 Canadians has Huntington's disease.

Symptoms usually appear in the late 30s, and every child of an HD sufferer has a 50-per-cent chance of developing the disease during the course of a lifetime.