This is the third part of a three-part series
There are no happy endings for those diagnosed with Huntington's disease.
The killing of Susan Miller by her Huntington's-afflicted husband in 2009 may have deepened one family's tragic encounter with the deadly neurodegenerative syndrome, but David Miller's story was always going to end in tears.
Now, the Times has learned the deadly disease may be more prevalent in British Columbia than previously thought.
Researchers at the University of British Columbia's world-renowned Centre for Huntington Disease say a new study suggests British Columbia has one of the highest rates of the disease in the world.
With around 15 people with Huntington's for every 100,000 residents, British Columbia "will have one of the highest published rates" in the world when the report is published later this year, UBC neurologist Dr. Blair Leavitt told the Times. That number is double what scientists once believed to be the average rate for Western countries. (It follows another recent study in the United Kingdom that put the rate there at 12.3 patients per 100,000-more than double the previous estimated prevalence.) It's a major finding-albeit not a positive one.
And there's even more, and equally disturbing, news.
Th UBC study will also show a significant number of Huntington's sufferers do not have a family history of the disease-something that could drastically alter perceptions of the tragic syndrome.
Huntington's is genetic. The general rule of thumb is that a child of a Huntington's patient has a 50 per cent chance of inheriting the faulty gene that causes the disease. The disease always leads to mental and physical decline and, given enough time, death. Those without a family history of Huntington's have been thought to be mostly in the clear. But that might not be true.
A higher rate than previously thought The reason lies in the way genes are passed on from parent to child.
The HTT is just one of our 20,000 genes.
For most of us, the Huntingtin gene, as it's more commonly known, is just another sub-microscopic part of the DNA that makes us human. Huntington's disease occurs when the HTT malfunctions and produces a flawed and toxic form of the normally benign Huntingtin protein. That protein, through a process that is not completely understood, leads to unstoppable physical and mental deterioration, often beginning in middle age. The decay leads to unstable and unpredictable thoughts and clumsy behaviour. It always ends in death.
(It's important to note Huntington's patients are no more predisposed to violence or crime than other people who might suffer from mental illnesses. Researchers say the symptoms can be effectively managed with drugs.) The Huntingtin protein's toxicity, or lack thereof, all depends on a glutamine residue in the HTT gene. Normally that residue repeats anywhere between six and 35 times in the gene. Genes with between 36 and 39 repeats sometimes develop the disease. Those with more than 40 almost always do. (Some people have more than 120 repeats.) The number of repeats is inherited, with some variability from generation to generation. But the Centre for Huntington Disease study suggests 10 per cent of Huntington's sufferers in B.C. have no family history of the disease. Leavitt says natural generation-to-generation mutations may cause someone with a parent with a high-but-normal number of repeats to possess a gene with 36 or more repeats-and thus develop Huntington's.
"Some of those 10 per cent are new mutations," Leavitt told the Times. "The new-mutation rate is higher than people thought in the past.
More common in England Leavitt and his fellow researchers say the rate is just one of a range of factors contributing to the higher-than-expected prevalence of Huntington's. "There are a number of factors all coming together-more testing, better diagnosis, aging population, new mutations that occur at a higher rate-all of which make this a more common disease than previously thought," Leavitt said.
Huntington's hits people at different times. (The age depends, in part on that all-important repeat count. More repeats mean it strikes at an earlier age.) As British Columbians live longer, Huntington's is being detected in more elderly people who would previously have either died before the disease surfaced, or not been diagnosed.
"With the aging population there's going to be more and more Huntington's disease diagnosed," Leavitt said.
He also speculated that British Columbia could have higher rates than other locations because the province was settled by people from portions of England where the disease is relatively common. Some of those settlers may then have passed on faulty Huntingtin genes to a growing number of descendants.
Raising local awareness The fact that some 700 people in British Columbia are believed to have Huntington's disease, may force health officials to increase local knowledge of the disease.
With the Centre for Huntington Disease, British Columbians are blessed with one of the best Huntington's research institutes in the world. Most of those diagnosed with the disease are referred to the clinic, which offers a range of services and can prescribe drugs to treat the symptoms of the disease.
But relatives of those with Huntington's say there is much less awareness of the disease in the general medical community. And sometimes that lack of familiarity can delay Huntington's sufferers' ability to access vital drugs that can delay the onset of symptoms and alleviate many of its physical and psychological effects.
Bill Kaminski, who lives in Chilliwack with two relatives who have Huntington's, has first-hand experience with the lack of knowledge in the medical community. He said his relatives were misdiagnosed multiple times before it was discovered they had Huntington's.
"The progression of the disease tends to fool practitioners," Kaminski told the Times. "Recognition is a problem because it tends to mimic a lot of symptoms of other diseases," he said.
Kaminski said he's seen everything from bipolar disease to bipolar disorder and Alzheimer's diagnosed instead of Huntington's.
"The knowledge is very limited," he said.
David Miller's mother-in-law Jean Anderson agreed. She said those who dealt with David in Chilliwack clearly weren't familiar with the disease.
"They didn't have a clue what to do in Chilliwack about Huntington's," she told the Times.
Leavitt said a lack of familiarity with the disease is understandable given that many doctors will go their whole career without seeing one case of Huntington's. New diagnoses are also rare; at this point, most patients have had a parent diagnosed in the past. And sometimes, the tell-tale physical jerkiness that is often an early symptom of Huntington's is preceded by mental problems often associated with more common diseases.
But Leavitt also says the knowledge of the disease is still sometimes lacking.
"It's something we all feel could be better," he said. "The diagnoses can be delayed and it can be difficult. We would say there is room for better awareness."
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