Genetic screening project to screen 100,000 Canadians for hereditary cancer, high cholesterol risks
Over the next five years, 100,000 people will be screened in OntarioOr genetic conditions that increase the risk of hereditary cancer and conditions associated with high cholesterol and heart disease, says the Princess Margaret Cancer Centre.
In what the hospital calls one of the largest population genomics studies in Canada, the project combines screening results to allow participants and their healthcare team to make decisions to potentially delay, reduce or prevent cancer and heart disease. Additionally, hospital researchers gain a rich dataset that they can combine with patient information, which can help address people at disproportionate health risk.
The first participants will be cancer patients at the hospital who may have genetic risks that could affect their treatment or how they are monitored, said Dr. Raymond Kim, medical director of early cancer detection at Princess Margaret.
“Yes, these patients have cancer, but we don’t know their genetic makeup,” Kim said. “Knowing their genetic makeup helps us see if we (Doctor) Have to be concerned about another cancer.”
to know of people genetic makeup Can alert doctors about risks and effects next steps in treatment, People with BRCA mutations are encouraged to start monitoring their breasts at age 20, Kim said. or if someone has the gene variant lynch syndrome, which is People with colorectal and other cancers may need a colonoscopy, he said.
Leslie Bourne, a patient who was a participant in an earlier research project at the hospital, was diagnosed in March 2020 with advanced ovarian cancer that had spread to the lining of her stomach. He was treated with surgery and chemotherapy.
Bourne did not have a strong history of cancer in his family, but he was screened for a variety of cancer-associated mutations.
“I received the news that I have a BRCA2 genetic mutation following the results of my surgery and biopsy,” Bourne said. “That was a shock. I had no idea.”
The BRCA2 gene provides instructions for making a protein that acts as a tumor suppressor. People with BRCA2 mutations have an increased risk of certain cancers, including breast, ovarian, prostate, pancreatic and melanoma.
Born Now is given a breast MRI and mammogram every year as part of monitoring. Without the genomic information, Kim said, he and his physicians would not have known it was needed.
Cast a wide net for genetic testing
Because family size is smaller on average than in previous generations, traditional methods of identifying high-risk families may not include many people, says Laura Palma, a certified genetic counselor at McGill University Health Center in Montreal, who is not involved in the project.
“Some of these Family It is not so easy to identify,” said Palma. “Expanding the network in terms of access to genetic testing may be the best strategy moving forward.”
Palma says it will be interesting to see the project’s findings and what participants do with the information, such as changes in eating habits or physical activity levels.
The genomic testing and care that follows will cost, and palma says Cost-effectiveness will not be immediately apparent.
“I think we need those studies in Canada to really see: can our system adopt this kind of model and does it make sense for taxpayers?” Palma said.
Two Saskatchewan sisters faced agonizing decisions to save their lives after genetic testing revealed they had a mutation that increased their chances of developing a deadly type of colon cancer.
Like Palma, Jenna Scott, co-director of the graduate program in genetic counseling at the University of British Columbia, welcomed the “fantastic” project.
According to Scott, the cost of genomic testing has gone down and it has become easier to use mouthwash instead of blood to collect a DNA sample. But they also have questions about scaling the project more broadly while understanding cultural needs.
“If I’m an Indigenous patient and I live in a rural remote community, how can I get a breast MRI? Is there any funding to help me get to urban centers where screening is done?” He said.
The researchers will share the results with the participants and hope that the data collected will be used to explore how useful this type of widespread screening might be and for whom. Kim’s goal is to enroll not only patients in Toronto’s University Health Network, but also patients referred by family physicians.
Kim said family members of patients, including those with familial hypercholesterolemia, an inherited condition associated with high cholesterol and cardiovascular risk, will be offered counseling, monitoring and individualized treatment when appropriate.
Helix, a biotechnology company based in San Mateo, California, is a partner in the project. Kim said the hospital’s research ethics board worked diligently to ensure people’s privacy was protected.
