DNA takes mystery out of medicine
New field of genomics helped crack patient's baffling case and shed light on future of health care
Asha Perera had to give up a musical career because of her body's reaction to certain medications. She suffers from polycystic ovarian syndrome, which causes a chemical imbalance in the body. 'My personality drastically changed,' she says.
Photograph by: Mark van Manen, PNG , Special To The Province
Asha Perera dreamed of a career in music.
Playing the piano had brought her joy since she was eight years old. She always turned to music for comfort.
She especially loved Mozart's Sonata in C Major. Its playful nature distracted her from life's problems.
About 20 years ago, Perera followed her passion to college, where she discovered a talent for singing. Caro mio ben, an emotional love song, quickly became one of her favourite melodies.
Then the insomnia and attacks of extreme anxiety began. Her suffering was traced to polycystic ovarian syndrome, which causes a chemical imbalance in the body. A doctor prescribed her a new medication but within hours of taking it she noticed problems with her hand-eye coordination. She was told she needed to take the drug for six months to improve her condition.
"As time went on, I couldn't even look at a piece of music and play," says Perera, whose real name The Province agreed not to disclose.
"My personality drastically changed. And when your body is the instrument and it's broken, you can't sing either," she says. "It completely derailed my life."
Perera switched majors and started taking classes in health psychology, participating in research experiments to learn more about herself. She tried dozens of different medications over the years, but continued to have severe adverse reactions to certain drugs. Doctors were baffled. Desperate for answers, Perera sent a blood sample to Genova Diagnostics, a genomic laboratory in the United States, which sent her a list of medications to avoid.
That was a turning point. "The test made me aware for the first time that there might be something genetic going on," Perera says. "It was such a relief to finally see something."
Further investigations by a genomics team at the University of British Columbia found that one of her genes had mutated in a way never seen before.
Perera's case illustrates how advances in genomics are helping doctors prescribe medications based on a patient's genetic information. This new field has a name: personalized medicine.
"One of the promises of personalized medicine is it will deliver the right medication to you, just for you," says Dr. Kendall Ho, director of the University of B.C.'s eHealth Strategy Office.
One reason health care is expensive is that doctors are currently prescribing treatments without really knowing what the patient's response will be, says Dr. Don Sin, the Canada Research Chair in chronic obstructive lung disease. "With personalized medicine, instead of treating a thousand patients and hoping 10 per cent will respond, we will know whether this therapy will work for you personally," he says.
This will lower health-care costs and help reduce severe side effects and prolonged hospitalizations, Sin says.
At the Prevention of Organ Failure Centre of Excellence in Vancouver, Sin is looking for genomic answers to chronic obstructive pulmonary disease, a condition affecting approximately 20 per cent of adults over the age of 40 in the Lower Mainland, he says.
Playing the piano had brought her joy since she was eight years old. She always turned to music for comfort.
She especially loved Mozart's Sonata in C Major. Its playful nature distracted her from life's problems.
About 20 years ago, Perera followed her passion to college, where she discovered a talent for singing. Caro mio ben, an emotional love song, quickly became one of her favourite melodies.
Then the insomnia and attacks of extreme anxiety began. Her suffering was traced to polycystic ovarian syndrome, which causes a chemical imbalance in the body. A doctor prescribed her a new medication but within hours of taking it she noticed problems with her hand-eye coordination. She was told she needed to take the drug for six months to improve her condition.
"As time went on, I couldn't even look at a piece of music and play," says Perera, whose real name The Province agreed not to disclose.
"My personality drastically changed. And when your body is the instrument and it's broken, you can't sing either," she says. "It completely derailed my life."
Perera switched majors and started taking classes in health psychology, participating in research experiments to learn more about herself. She tried dozens of different medications over the years, but continued to have severe adverse reactions to certain drugs. Doctors were baffled. Desperate for answers, Perera sent a blood sample to Genova Diagnostics, a genomic laboratory in the United States, which sent her a list of medications to avoid.
That was a turning point. "The test made me aware for the first time that there might be something genetic going on," Perera says. "It was such a relief to finally see something."
Further investigations by a genomics team at the University of British Columbia found that one of her genes had mutated in a way never seen before.
Perera's case illustrates how advances in genomics are helping doctors prescribe medications based on a patient's genetic information. This new field has a name: personalized medicine.
"One of the promises of personalized medicine is it will deliver the right medication to you, just for you," says Dr. Kendall Ho, director of the University of B.C.'s eHealth Strategy Office.
One reason health care is expensive is that doctors are currently prescribing treatments without really knowing what the patient's response will be, says Dr. Don Sin, the Canada Research Chair in chronic obstructive lung disease. "With personalized medicine, instead of treating a thousand patients and hoping 10 per cent will respond, we will know whether this therapy will work for you personally," he says.
This will lower health-care costs and help reduce severe side effects and prolonged hospitalizations, Sin says.
At the Prevention of Organ Failure Centre of Excellence in Vancouver, Sin is looking for genomic answers to chronic obstructive pulmonary disease, a condition affecting approximately 20 per cent of adults over the age of 40 in the Lower Mainland, he says.
Lung attacks, which start to occur as the disease worsens, are a leading cause of hospitalization in B.C. Sin is hoping to develop a simple blood test that will monitor when patients are most at risk for these attacks, so they can be treated before hospitalization is required.
"For most drugs, less than half of patients who receive a particular pharmaceutical actually have a positive response to that drug," says Brad Popovich, chief scientific officer at Genome B.C., a non-profit research organization that seeks new benefits for humanity through DNA science.
"And furthermore, there's a small set of patients who receive drugs, in particular pharmaceuticals, that don't get any therapeutic benefit but even more alarmingly, have an adverse reaction."
Side effects can be as extreme as deafness and heart failure, he says.
One example of successful personalized medicine is HIV treatment. A lab test is used to sequence the virus in an HIV patient, which helps predict the most effective drugs for an individual.
"Twenty years ago, HIV was a fatal disease, but now with this personalized approach to treatment, these patients continue to have a healthy life," Popovich says.
Personalized medicine is also used to treat breast cancer. The drug Herceptin is very effective on women who test positive for a particular genetic change, says Popovich, but it has virtually no effect on patients who test negative.
"There are many people in Vancouver who have benefited from this therapy, and those numbers are just going to continue to grow exponentially," Popovich says.
Researchers hope that patients' electronic health records, including their biological and physical characteristics, will ultimately be linked with their genetic information. This will allow scientists to mine the data to determine which conditions are genetic and which are environmental.
"Your genome sequence is finite and stable, so once you determine that sequence, it becomes a very good record to hang everything else against," says Dr. Stephen Scherer, director of the Centre for Applied Genomics at the Hospital for Sick Children in Toronto.
"In the best case scenario, you would have your genome sequenced just after you were born, and it would sit in the big giant database," he says.
Doctors could compare the genetic data of patients suffering from similar medical problems to predict whether the problem will go away or will require certain medications, Scherer says.
However, Micheal Vonn, policy director at the B.C. Civil Liberties Association, is alarmed that a huge privacy risk would be created if electronic health records were to be linked to genetic information.
"This is a hugely rich data set," she says.
"You can't anonymize your genome. It's ludicrous. It's the most clearly identified piece of you, and you can track whole families through this."
The idea of linking this sensitive information and storing it in a cloud is terrifying, she says.
"For most drugs, less than half of patients who receive a particular pharmaceutical actually have a positive response to that drug," says Brad Popovich, chief scientific officer at Genome B.C., a non-profit research organization that seeks new benefits for humanity through DNA science.
"And furthermore, there's a small set of patients who receive drugs, in particular pharmaceuticals, that don't get any therapeutic benefit but even more alarmingly, have an adverse reaction."
Side effects can be as extreme as deafness and heart failure, he says.
One example of successful personalized medicine is HIV treatment. A lab test is used to sequence the virus in an HIV patient, which helps predict the most effective drugs for an individual.
"Twenty years ago, HIV was a fatal disease, but now with this personalized approach to treatment, these patients continue to have a healthy life," Popovich says.
Personalized medicine is also used to treat breast cancer. The drug Herceptin is very effective on women who test positive for a particular genetic change, says Popovich, but it has virtually no effect on patients who test negative.
"There are many people in Vancouver who have benefited from this therapy, and those numbers are just going to continue to grow exponentially," Popovich says.
Researchers hope that patients' electronic health records, including their biological and physical characteristics, will ultimately be linked with their genetic information. This will allow scientists to mine the data to determine which conditions are genetic and which are environmental.
"Your genome sequence is finite and stable, so once you determine that sequence, it becomes a very good record to hang everything else against," says Dr. Stephen Scherer, director of the Centre for Applied Genomics at the Hospital for Sick Children in Toronto.
"In the best case scenario, you would have your genome sequenced just after you were born, and it would sit in the big giant database," he says.
Doctors could compare the genetic data of patients suffering from similar medical problems to predict whether the problem will go away or will require certain medications, Scherer says.
However, Micheal Vonn, policy director at the B.C. Civil Liberties Association, is alarmed that a huge privacy risk would be created if electronic health records were to be linked to genetic information.
"This is a hugely rich data set," she says.
"You can't anonymize your genome. It's ludicrous. It's the most clearly identified piece of you, and you can track whole families through this."
The idea of linking this sensitive information and storing it in a cloud is terrifying, she says.
Researchers see a future in which genomics rises above these concerns.
"If everyone had their genome sequence on a disk they carried every time they went to the doctor, this wouldn't be such a novel thing," says Michael Szego, ethicist for the Personal Genome Project Canada, which was launched by the Centre for Applied Genomics in December. "The reason why this is so controversial right now is because it's new." The Personal Genome Project Canada is building an Internet database of Canadian volunteers' genome sequences and health information for scientists around the world. Because anybody will have access to the raw data, researchers will not need to seek ethical approval to use it.
"By putting this information out there and making it available, we're allowing scientists who may not usually have access to this kind of information to play with it and come up with novel tools to look at the data in different ways," Szego says.
"And that's what's exciting about building an open-access infrastructure."
More than 500 people initially volunteered, so currently individuals who can cover the $4,000 cost are preferred. Researchers are hoping to have 30 genomes sequenced in the first year of the project, Scherer says, and the goal for the worldwide effort is 100,000.
Participants must give a blood sample and submit baseline trait data, including their personal medical history, allergies and ethnicity. It takes about a week to prepare and sequence the genome, and a standard analysis takes a further two weeks.
Individuals must undergo a rigorous consent process prior to their participation, which includes discussing possible implications with their families, writing an online test and genetic counselling after receiving their results.
In a different study, Scherer recently sequenced 32 Canadians with autism and their families to study the genetic basis of the condition.
"But the problem is we do these studies of specific diseases and we don't have anything to compare them against," he says. "We need to have a selection of control data from the healthy population."
However, British Columbians need to carefully consider the risks before participating in genetic tests.
While other countries including the U.S. and U.K. have passed laws protecting citizens from genetic discrimination, Canada has yet to do so. Individuals who have undergone genetic testing must share their results when required by life insurers, who can use this information to refuse eligibility.
"With the amount of information about you out there, somebody could identify that you're at risk for certain diseases, and there may be employment and insurance problems," Szego says. "There's no guarantee, no promise of privacy." Participants might also find information about themselves that they find troubling, such as a high risk for a disease, Szego says.
Popovich says the potential benefits of genomics are enormous, but certain issues still need to be considered.
"Do we have the protections in place as a society in British Columbia to protect people from the misuse of our genetic information?" he asks. "I think the verdict is still out on that."
Despite the risks, Perera is still willing to give the Personal Genome Project Canada a chance.
Researchers haven't been able to compare Perera's South Asian genetic data to a "healthy" sample, because they don't have enough data for her particular ethnic group, a problem the genome project is trying to address.
By volunteering, she hopes that researchers will take an interest in her case.
"If people from different parts of the world can have access to genetic information, we might find answers faster," she says.
Jules Knox wrote this series as a result of winning the Jeani Read-Michael Mercer fellowship for Langara College journalism graduates, endowed in honour of the late Province columnist Jeani Read. John Fuller was her editor.
"If everyone had their genome sequence on a disk they carried every time they went to the doctor, this wouldn't be such a novel thing," says Michael Szego, ethicist for the Personal Genome Project Canada, which was launched by the Centre for Applied Genomics in December. "The reason why this is so controversial right now is because it's new." The Personal Genome Project Canada is building an Internet database of Canadian volunteers' genome sequences and health information for scientists around the world. Because anybody will have access to the raw data, researchers will not need to seek ethical approval to use it.
"By putting this information out there and making it available, we're allowing scientists who may not usually have access to this kind of information to play with it and come up with novel tools to look at the data in different ways," Szego says.
"And that's what's exciting about building an open-access infrastructure."
More than 500 people initially volunteered, so currently individuals who can cover the $4,000 cost are preferred. Researchers are hoping to have 30 genomes sequenced in the first year of the project, Scherer says, and the goal for the worldwide effort is 100,000.
Participants must give a blood sample and submit baseline trait data, including their personal medical history, allergies and ethnicity. It takes about a week to prepare and sequence the genome, and a standard analysis takes a further two weeks.
Individuals must undergo a rigorous consent process prior to their participation, which includes discussing possible implications with their families, writing an online test and genetic counselling after receiving their results.
In a different study, Scherer recently sequenced 32 Canadians with autism and their families to study the genetic basis of the condition.
"But the problem is we do these studies of specific diseases and we don't have anything to compare them against," he says. "We need to have a selection of control data from the healthy population."
However, British Columbians need to carefully consider the risks before participating in genetic tests.
While other countries including the U.S. and U.K. have passed laws protecting citizens from genetic discrimination, Canada has yet to do so. Individuals who have undergone genetic testing must share their results when required by life insurers, who can use this information to refuse eligibility.
"With the amount of information about you out there, somebody could identify that you're at risk for certain diseases, and there may be employment and insurance problems," Szego says. "There's no guarantee, no promise of privacy." Participants might also find information about themselves that they find troubling, such as a high risk for a disease, Szego says.
Popovich says the potential benefits of genomics are enormous, but certain issues still need to be considered.
"Do we have the protections in place as a society in British Columbia to protect people from the misuse of our genetic information?" he asks. "I think the verdict is still out on that."
Despite the risks, Perera is still willing to give the Personal Genome Project Canada a chance.
Researchers haven't been able to compare Perera's South Asian genetic data to a "healthy" sample, because they don't have enough data for her particular ethnic group, a problem the genome project is trying to address.
By volunteering, she hopes that researchers will take an interest in her case.
"If people from different parts of the world can have access to genetic information, we might find answers faster," she says.
Jules Knox wrote this series as a result of winning the Jeani Read-Michael Mercer fellowship for Langara College journalism graduates, endowed in honour of the late Province columnist Jeani Read. John Fuller was her editor.
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