Genetic discoveries have made huge strides in recent decades. These advances and new technologies are revolutionizing our access to genetic testing. Some companies offer “at-home” genetic tests that make it as simple as sending in a mouth swab to the company. Accredited labs also offer tests for specific genes believed to be linked to various diseases.
These tests can provide insight into your risk for certain diseases. However, not all genes cause disease, and care must be taken when creating a screening test for a given gene. Clinicians who are not experts in genetics or a particular disease may also place undue faith in lab tests: they may assume that because a lab is offering testing for a specific gene, it must be linked to a disease.
An international team led by Toronto General Hospital Research Institute Scientist and Peter Munk Research Chair in Cardiovascular Molecular Medicine Dr. Michael Gollob recently used an evidence-based framework to investigate the appropriateness of genetic tests. The team focused on genetic tests used for Brugada syndrome—a rare heart rhythm disease that puts around one in 2000 people at risk for sudden cardiac death.
For the study, the researchers included a group of 21 genes for Brugada Syndrome that are currently tested by labs in the United States and internationally. Three teams independently reviewed each gene to determine whether sufficient evidence exists to link them with Brugada syndrome.
Only one gene, known as SCN5A, was definitively linked to Brugada syndrome—while evidence was lacking for the other 20 genes. All three teams independently agreed on these results.
These results are troubling because they reveal that many genetic tests may fail to provide real insights. Use of these dubious tests could lead to incorrect diagnostic conclusions, unnecessary testing, treatments and anxiety and stress for patients and families.
As to why the laboratories offer so many unproven tests, Dr. Gollob remarks that “Laboratories do not have to justify the inclusion of genes for clinical testing. It’s possible that the increasingly competitive marketplace and a ‘more is better’ mentality has led to rapidly expanding gene panels. Our findings indicate that more rigorous standards are required to ensure that genetic tests are meaningful.”
This work was supported by the US National Human Genome Research Institute. Dr. Gollob is supported by a Peter Munk Research Chair in Cardiovascular Medicine from the Toronto General & Western Hospital Foundation.
Hosseini SM, Kim R, Udupa S, Costain G, Jobling R, Liston E, Jamal SM, Szybowska M, Morel CF, Bowdin S, Garcia J, Care M, Sturm AC, Novelli V, Ackerman MJ, Ware JS, Hershberger RE, Wilde AAM, Gollob MH (Chair); NIH-Clinical Genome Resource Consortium. Reappraisal of Reported Genes for Sudden Arrhythmic Death: An Evidence-Based Evaluation of Gene Validity for Brugada Syndrome. Circulation. 2018 Jun 29. pii: CIRCULATIONAHA.118.035070. doi:10.1161/CIRCULATIONAHA.118.035070.
The role of insulin in improving the ability of the immune system to fight infection has been described for the first time by Toronto General Hospital Research Institute (TGHRI) scientists.
The research findings were published in Cell Metabolism by first author Dr. Sue Tsai, postdoctoral fellow, and senior authors, Dr. Daniel Winer, TGHRI Scientist and Anatomical Pathologist at University Health Network; and Dr. Shawn Winer, Anatomical Pathologist at St. Michael's Hospital.
A fast and effective immune response protects us against infections, such as influenza. T cells are at the heart of this process: they divide rapidly and secrete chemical messenger proteins (cytokines) that direct the rest of the immune system to destroy the virus.
A lot of work has been done on insulin’s role in regulating blood sugar and how the body turns it into energy, yet little is known about how it affects the immune system.
The research team designed T cells that could no longer respond to insulin. They then observed what happened to the T cells after they exposed them to a flu virus.
They discovered that insulin gives the immune system the boost needed to fight the infection. Without it, the T cells were unable to effectively destroy the virus.
"T cells are at the heart of so many diseases," says Dr. Tsai, "Understanding them at the cellular level will give us the best opportunity to discover new pathways to target for new therapies." In the future, she says, we could harness this insulin signalling pathway to either boost the immune response to create vaccines, for example, or dampen it to heal inflammatory illnesses such as arthritis, ulcerative colitis and Crohn's disease.
Tsai S, Clemente-Casares X, Zhou AC, Lei H, Ahn JJ, Chan YT, Choi O, Luck H, Woo M, Dunn SE, Engleman EG, Watts TH, Winer S, Winer DA. Insulin Receptor-Mediated Stimulation Boosts T Cell Immunity during Inflammation and Infection. Cell Metab. 2018 Aug 22. pii: S1550-4131(18)30504-7. doi:10.1016/j.cmet.2018.08.003.
This work was supported by the Canadian Institutes of Health Research, Diabetes Canada, the J.P. Bickell Foundation Grant, the Banting and Best Diabetes Centre at the University of Toronto, and the Toronto General & Western Hospital Foundation. D Winer holds a Tier 2 Canada Research Chair in Immunometabolism. M Woo holds a Tier 2 Canada Research Chair in Signal Transduction in Diabetes Pathogenesis.
A University Health Network spin-off company known as Acumyn Inc. was recently acquired by global radiotherapy giant Elekta.
Acumyn was created by UHN’s Technology Development and Commercialization (TDC) office to commercialize AQUATM, a software platform developed at Princess Margaret by a team led by Dr. Daniel Letourneau. The clinical software platform brings all the demanding quality assurance tests and calibrations a radiotherapy clinic needs to perform into a single place, helping to manage and automate these complex tasks.
AQUA helps manage department workload and scheduling, reduces the likelihood of machine down-time and patient delays, and makes it easier to maintain regulatory compliance, while saving time. “There was a clear need to better manage quality assurance activities in the radiation therapy clinic, and we saw that this was a gap in the broader market,” says Dr. Daniel Letourneau, Associate Head, Medical Physics at Princess Margaret, and Co-Founder and CTO at Acumyn.
“[AQUA is] a global commercial success that came from the need to assure Princess Margaret cancer patients get the safest, highest level of care possible,” says Dr. David Jaffray, Director of the Techna Institute, Executive Vice-President of Technology and Innovation at UHN, and Acumyn Co-Founder.
Techna used its medical device engineering and product development expertise to help Acumyn “productize” AQUA. Techna’s services included project management; documentation to achieve ISO 13485 and 9001 certification; the creation of marketing materials, a user manual and website; user interface design; and financial services. Techna’s professional services provided the expertise needed to advance the software platform without requiring the small Ontario-based start-up to hire full-time employees for every role. This expertise, combined with real-world evidence and product refining provided by Princess Margaret and the support of TDC, helped Acumyn to scale-up and succeed. “TDC took the calculated risk, formed the UHN start-up and afforded the CEO the requisite business and financial support so that the value created in the company could be captured optimally,” underlines Mark Taylor, TDC’s Team Lead.
With this multi-million-dollar acquisition, Elekta plans to integrate AQUA more broadly across its portfolio while further developing its quality assurance offering through the expertise that the Acumyn team brings with it. “This will accelerate the uptake of safe radiotherapy worldwide,” concludes Dr. Mary Gospodarowicz, Medical Director of the Princess Margaret Cancer Centre. Adds John Reid, Director of TDC at UHN, “Acumyn’s success story is an example of UHN’s ability to discover, develop and deliver commercially interesting research, which not only attracts top investors and management teams, but also enriches the Toronto ecosystem.”
A new study from researchers at University Health Network recommends that all patients with psoriatic arthritis (PsA) be screened for inflammation in their back joints, regardless of whether or not they have back pain.
PsA typically occurs in people with a skin condition known as psoriasis. PsA is characterized by inflammation and pain primarily in the joints of the hands, feet, knees, ankles, wrists, elbows or hips. If left untreated, the disease can lead to irreversible joint damage and disability.
In some patients, PsA can also cause inflammation and pain in the joints of the back, which is referred to as axial arthritis. When axial arthritis occurs in patients, it can signal the presence of more severe forms of PsA—forms that could benefit from treatment with more potent medications.
“Despite its importance, accurately detecting axial arthritis in patients with psoriatic arthritis is difficult,” says Dr. Vinod Chandran, an Affiliate Scientist at the Krembil Research Institute.
“There is no widely accepted definition or test for axial disease in psoriatic arthritis. Instead, when chronic back pain is identified, a rheumatologist will rely on his or her professional judgement to predict whether it is caused by axial arthritis or by other factors, such age, excess weight or osteoarthritis.”
In the new study, Dr. Chandran evaluated the accuracy of rheumatologists’ prediction in diagnosing axial arthritis in PsA patients.
He enrolled 171 PsA patients with or without back pain into his study. A rheumatologist judged whether or not a patient’s back pain was caused by PsA after considering the patient’s history and physical examination. Additionally, each patient received a back X-ray to detect inflammation in their back joints.
By comparing results of the X-rays to the predictions made by rheumatologists, Dr. Chandran found that rheumatologists are not very good at detecting axial arthritis in PsA patients. Moreover, he showed that over 30% of PsA patients with axial arthritis detected by the X-ray images experienced no back pain at all.
“Our findings suggest that rheumatologists should consider conducting back X-rays or MRI in all patients with PsA regardless of the presence or the nature of their back pain. To date, imaging appears to be the best way to detect axial involvement. This approach would also enable rheumatologists to better identify patients with potentially severe PsA early so that their treatments could be better optimized to slow joint damage.”
This study was supported by the Krembil Foundation and the Toronto General & Western Hospital Foundation.
Yap KS, Ye JY, Li S, Gladman DD, Chandran V. Back pain in psoriatic arthritis: defining prevalence, characteristics and performance of inflammatory back pain criteria in psoriatic arthritis. Ann Rheum Dis. 2018 Aug 4. pii: annrheumdis-2018-213334. doi: 10.1136/annrheumdis-2018-213334.
Welcome to the latest issue of Research Spotlight.
This newsletter highlights top research advancements across UHN and from over 450 researchers appointed at five research institutes. As Canada’s largest research hospital, UHN is a national and international source for discovery, education and patient care.
Stories in this month’s issue:
● ORIGINS OF LEUKEMIA REVEALED: Genetic screening tool has been developed that can predict risk for leukemia in healthy people.
● SETTING SIGHTS ON PARKINSON DISEASE: AI analysis of short videos of patients can help to effectively gauge treatment response.
● KEEP CALM TO FIND PEACE: New UHN support program for those with advanced cancer shown to reduce depression and anxiety.
● CAUGHT OFF GUARD: Study shows that heart health is not monitored according to risk in women with breast cancer.
● UNTANGLING BRAIN DISORDERS: UHN researchers contribute to international study on the genetic basis of brain disorders.
● UHN LAUNCHES KREMBIL BRAIN INSTITUTE: New institute will harmonize and integrate clinical and research programs in neuroscience.