Jeffrey Carroll is about to learn whether the drug he is dripping into the brains of mice works. These are no ordinary mice; they are bred to mimic Huntington's disease. Mr. Carroll is no ordinary scientist; he carries the gene for that devastating neurological disease, which, despite more than a century of research, still has no cure or treatment. It is here, in the biggest Huntington's laboratory in Canada, that Mr. Carroll hopes to change all that - and alter his own genetic destiny.
Research is moving fast, but the question is whether it will be fast enough for Mr. Carroll, who is living out the scientific version of Beat the Clock: Unless a treatment is found, he will eventually show the telltale symptoms of slurred speech, uncontrolled ticks and jerks as early as his late 40s.
"Killing you is not the cruel part of this disease. It destroys your personality and turns you into an object of horror for your family," explains the 30-year-old, who's at work on his PhD in neuroscience. "Even if they love you, nobody can watch it and not be horrified."
No one knows this better than Mr. Carroll, a slender, fit man who looks like the poster child for good health. He knows what awaits him: Huntington's disease killed his grandmother and, more recently, his mother, Cindy Carroll, who died in December at the age of 54. Near the end, she had to be placed on floor mats in the nursing home in a Washington state town, so severe was her violent, involuntary thrashing.
This is the inherent viciousness of the disease: A child who watches it slowly kill a parent has a 50-per-cent chance of developing it, creating this perpetual cycle of grief and suffering.
"It is the most profound thing. You know how you probably are going to die," Mr. Carroll says. "You watched somebody you love die the exact same way."
More than 3,000 Canadians have the incurable brain disorder and 18,000 more are at risk of developing it, according to figures from the Huntington Society of Canada. The disease typically stalks people in their 30s or 40s, snatching bits and pieces of them in the form of forgetfulness, clumsiness and slurred speech. Involuntary jerks and ticks make sufferers the object of stares.
A patient with Huntington's is trapped inside a body that can perceive but not express, as if their very being is slowly extinguished. In the late stages, patients are left incontinent, unable to walk, talk, think or swallow. But it takes many agonizing years to get to that point. Death comes 10 to 25 years after diagnosis in the form of an infection or other complications.
The disorder can be traced to the Middle Ages. One of its earliest names - "chorea," from the Greek word for dance - described how these patients uncontrollably writhe, turn and twist. But it wasn't until 1872, when U.S. physician George Huntington wrote about a rare illness, "an heirloom from generations away back in the dim past" that the disease got its present name.
He was the first to write about the disease's three distinct features: It is hereditary, appears in adult life and brings a tendency to insanity or suicide. Others have referred to it as "Woody Guthrie disease," as the famous American folk singer died of it in 1967.
About 135 years after it got its name, the genetics of the disease are well known, but it has not translated into a cure.
The mutant gene sits on the short arm of our fourth chromosome. There, the letters of the genetic alphabet C-A-G can normally repeat as many as 35 times in a row. Those with 36 repeats or more will develop Huntington's disease, should they live long enough. The greater number of C-A-G repeats, the earlier the disease will typically strike. Mr. Carroll's C-A-G is 42, which means he could start showing symptoms as early as the age of 49.
"Certainly, given enough time, I know how awful it is going to be," he says. "It's the only thing, I often think, that makes me different … the knowledge that I am one of them, that I am going to die. I know how I am going to die."
Put to the test
The genetic test for Huntington's disease has been available since 1993 and is covered by public health care, yet only 18 per cent of Canadians at risk take it, according to figures from the Huntington Society.
"I guess they feel they would rather not have this information because there isn't anything they can do to change it," says Joanne Honeyford, manager of clinical genetics at the North York General Hospital in Toronto.
Marriages can crumble under the weight of a positive test result. Dreams of having children vanish. There are worries about how an employer might react. And there are the very real possibilities of being unable to obtain life and long-term-disability insurance.
Adult children are not always aware that Huntington's disease runs in the family. Sure, there may have been a tragic story about a grandparent who was placed in a psychiatric hospital or committed suicide, but no one mentioned Huntington's. Though it passes through generations, knowledge of it may not.
In the Carroll family, the children knew that their maternal grandmother died of a neurological disease that was also, surprisingly, starting to affect their mother, Cindy, in her mid-40s. "Some of us saw the little things," says Ben Carroll, 26, Jeffrey's brother, who lives in Seattle. "I saw the Post-it notes, the jerks while driving and forgetting an old friend's name."
Jeffrey Carroll decided to undergo the test in 2003, wanting the certainty of knowing what the future held. He had already been through the physical - he had no neurological symptoms of the disease - and he had undergone psychological counselling. He was 25, married and an undergraduate biology student working in a laboratory. He was as ready as he ever would be.
On July 21, 2003, on a clear Vancouver day, Mr. Carroll showed up for his appointment with his wife, Megan Carroll, then 28.
The physician unfolded the piece of paper and read the test result out loud. In one brief moment, he learned he tested positive for the gene. Megan let out a noise she described as something between a gasp and a sob.
"And Jeff," she recalls, "asked for a job."
Mr. Carroll told the doctor that he was keen to be involved in finding a treatment. He wanted to help.
That evening, the couple dined at an upscale seafood restaurant in Vancouver. The news, they figured, merited the eight-course tasting menu. To casual observers, they appeared to be celebrating. When the server asked what the special occasion was, Mr. Carroll, in his usual forthright way, said they had received tragic medical news. It was an awkward moment, relieved somewhat by a free round of drinks.
Some time afterward, Mr. Carroll caught up with Michael Hayden, a physician and geneticist who runs Canada's biggest laboratory on Huntington's disease, where 20 people - half the staff - are devoted to its research.
Dr. Hayden, now director of the University of British Columbia's Centre for Molecular Medicine and Therapeutics, began studying the disease in 1976, when he saw sufferers being abandoned and neglected in his native South Africa.
"Once you get involved in Huntington's disease, it doesn't let you go," he says. "The human challenges are so profound, the scientific challenge is so profound and the need to do something was so profound, you couldn't let it go."
Even so, bringing Mr. Carroll into the laboratory was not an easy decision.
"We work with brains from people with Huntington's disease," Dr. Hayden said. "How would he cope? How would he cope with failure or the worry that research wasn't going as fast as it could? Would that truly be in his best interest?"
In the end, it was a group decision. The staff couldn't help thinking how meaningful it would be if their colleague was involved in finding a cure.
"He's making great progress, but it's slow. Research is slow," Dr. Hayden says. "It's filled with a few steps forward and one step back. I always worry when we take one step back. I want to protect him from that."
Dr. Hayden believes that a treatment will be ready for testing on humans five years from now. He envisions more than one drug will be involved, much the way cancer therapy has evolved.
"I hope we're going to prevent this illness, but I would be very happy to delay onset for 20, 30, 40 years," he says. "Jeff is not ill yet, but if we don't do anything, he will be ill one day. Our time is short."
On the bench
The Hayden laboratory sits far back from a busy street on the west side of Vancouver. Here on the second floor of a building at the Centre for Molecular Medicine and Therapeutics, part of the Child & Family Research Institute, scientists work long hours.
On one wall sits a large, stainless-steel-and-glass fridge. Inside, there are plastic containers of bovine albumin. Next to it, in another jar, sits the brain of mouse, suspended in liquid. A sign taped to the outside of the fridge and written in black magic marker warns staff not to leave food or drinks there.
Virtually every drug that is placed in a person's mouth has started in a laboratory like this, where scientists work "on the bench." It is gruelling work with punishing hours and for those who do it, there is nothing like it.
At one of these benches sits Mr. Carroll, who always seems in a hurry: He talks, walks and thinks fast. One senses that he is cramming life the way a student crams for an exam. No one's deadline in this laboratory is more pressing than his.
"For the patient and [family member]Jeff, I want a drug right now," he says. "For the scientist in me, at work … I don't think about pills. I think I just want to know. It's an intellectual problem. It's been like you've been working on a Rubik's Cube for 10 years and you just want to solve it."
The big break happened in the laboratory last year, when Dr. Hayden altered the mutant protein so that it could not be cut by the molecular scissors of an enzyme called caspase 6. These mice showed no symptoms of Huntington's and displayed normal brain function. It was a huge discovery that suggests that caspase 6 plays a significant role in the disease.
"All the data would suggest that caspase 6 is the bad guy," says Rona Graham, lead author on that study. "I am in the process of validating that … but it is looking like a key player."
The huntingtin protein (its name is spelled differently than the disease) is like a necklace, made up of beads of amino acids. Those who carry the Huntington's gene have extra beads on that necklace. Caspase 6 cuts the mutant protein in a spot called aa586, which unleashes what is believed to be a toxic fragment.
If scientists can find a drug to inhibit that cutting action or make it cut less frequently, they could delay, or possibly even prevent, the disease.
That is where Mr. Carroll's work comes in.
He is testing a compound, the name of which he does not want to reveal until he publishes his research, likely next year. When he gave that compound to mice for four weeks, it reduced the amount of scissor-cutting enzyme, caspase 6, by half. Four weeks after that, when the mice have had no more of the compound, that result stays constant.
But two questions remain: Is half enough? And how long does that reduction last?
"It's neat, it works, but still we haven't proven anything that makes HD better," says Mr. Carroll, with the cool detachment of a scientist.
The next phase of the experiment will be to treat mice who have lesions on their striatum, a part of the brain that suffers some of the most severe loss of neurons in those with Huntington's. He wants to see what compound, if any, has an effect on the size of the lesions.
His research is only one of several scientific avenues being pursued. There are efforts to knock out the mutant protein altogether. Fetal nerve cells have been transplanted into the brains of a few Huntington's patients. And there is extensive study on why neurons die.
What is known is that Huntington's causes a protein to be malformed and prone to clumping in the brain, which kills nearby nerve cells. The areas of the brain most affected are the cells of the basal ganglia, responsible for co-ordinating movement, and the cortex, which controls memory, perception and thought.
"The genetic flaw was quite obvious, but the big problem is the size of the protein the mutation is in," says Ray Truant, chairman of the Huntington Society of Canada's scientific advisory board. "It is roughly 10 times bigger than the normal protein, it's in every cell, it's required for development. Whatever this protein does, it's essential."
Despite the difficulties, Dr. Truant, associate professor in the department of biochemistry and biomedical sciences at McMaster University in Hamilton, shares the optimism of Dr. Hayden. "I'm optimistic there is going to be a major breakthrough in the next five years."
'Do the math'
Life has been particularly sweet for Mr. Carroll over the past 15 months. When he learned he carried the Huntington's gene, he thought that fatherhood was out of the question. But when he heard about pre-implantation genetic diagnosis, which combines genetic screening with in-vitro fertilization, that all changed.
He and his wife decided to tackle this high-tech fertility treatment as a way to ensure they do not have a child who would ultimately carry the disease. It all worked - two unaffected embryos that did not carry the genetic mutation were implanted and twins, a boy and a girl, were born on June 27, 2006.
Blond with milky white skin, Billie and Elijah Carroll look every bit like Gerber babies. They are learning to walk and talk. But even these wondrous moments with children are clouded by Mr. Carroll's genetic time bomb. The decision every parent faces - how to balance work and home life - weighs more heavily on him.
"I can't do things like other people do like skip your kids and say, 'Oh, I'll catch up later,'" he says. "I have one chance at everything."
Mr. Carroll is a stunningly bright scientist, but his career will almost certainly be stunted, because his working brain will run out of time. "I'm never going to be a tenure-track professor," he says matter-of-factly. "Unless there's a cure, I don't have time for that. Do the math."
He quickly runs through the numbers - one or two years to finish his PhD, four or five more to be a postdoctorate fellow. If he is very lucky, he will be getting his first grant in his early 40s.
"For me, in my planning my career and my life, I have to plan on dying at 45," he says, before quickly correcting himself. "Now, I won't be dead then, but I will be useless as a provider and a father."
Alicia Semaka, a PhD student in medical genetics, quickly adds: "You will still be a father. The love will still be there."
Beyond the pale
No matter how smart or educated they are, no matter how many their accomplishments, people with Huntington's disease all end up in the same spot. Nowhere is that more clear than at Runnymede Healthcare Centre in Toronto, one of a half-dozen hospitals in Canada that specializes in caring for these patients.
Staff do it in an 1908 schoolhouse that has been modified to become a complex, continuing-care hospital.
In the basement, patients work on crafts, making autumn leaves, using the colours of crimson and orange, trying to stay inside the pencilled lines. Even the patients talk about themselves in the past tense: One of them says she can draw well because she "used to" be an artist.
On the main floor, Liz Manique visits her father, Alberto Manique. Family photographs pinned to a board near his bed tell a story of a vigorous, handsome man who worked in construction, doing plastering and drywall. There are photos of him on vacation with his shirt off, bearing a strong chest. Today, there sits a red paper heart with the words "father" and "husband" written across them.
Taped to the wall near his bed is a black-and-white copy of what appears to be a medical drawing. It explains to caregivers how to feed Mr. Manique so he does not choke on his food. At 59, he has had the disease for 18 long years. A seat belt and lap restraints in a special padded chair ensure his involuntary kicks don't thrust him out of the chair.
"He was so strong, you would never think he would end up where he is now," Ms. Manique says. (She took the genetic test and found she did not carry the Huntington's gene.) Only when she rubs her father's face with her hand and speaks Portuguese, does he respond through awkward, gangling movement. His eyes rarely focus on her.
This haunting reality is what Mr. Carroll and his wife know lies ahead.
"It's scary sometimes," says Megan Carroll, now 32. "One of the first times we went to see his mom, I just lost it. … I had left the room, knowing my husband is going to possibly be this way some time in his life."
Cindy Carroll, whose happiest times were as a mother to six kids, spent her last hours writhing on floor mats and sick with an infection. Mr. Carroll placed Elijah, then six months old, in the crook of her neck, hoping the baby smell would give her some peace. It may have lasted seconds or minutes, but it was the only time during that visit that she stopped writhing.
When Mr. Carroll thinks of his mother's death, he talks of how he will cope with what the future holds. That's when euthanasia talk comes up.
Dave Richards of Britain heightened awareness of Huntington's last year, but not because he made a discovery: He sipped a lethal drink of barbiturates at a Swiss clinic, where voluntary euthanasia is legal.
Mr. Carroll says he has "respect for people who have the guts to say this is how I want to go," adding that it is a way to spare loved ones of the brutal reality of the disease.
"Would you die to spare your kids something so horrible?" Mr. Carroll asks. "I would. If you knew that every Christmas and every Easter and every birthday, they were going to come and congregate around your nursing home bed and talk to you, would you kill yourself? I would."
All voluntary euthanasia would do, he said, is eliminate one to two years of rapid deterioration and save his children from remembering him as a "slobbering, incontinent, mutant mess."
But he is nowhere near there yet. And if he has his way, he never will be. He wants to find a treatment or cure not only for himself and other sufferers, but also for his younger brother, Ben, 26, who tested positive for the gene almost a year ago.
It's a daunting exercise, but as Megan Carroll says, "If anybody's going to figure it out, it's going to be Jeff."
Lisa Priest writes on health issues for The Globe and Mail.