Why are we doing this research?
The Cardiac Genome Clinic (CGC) study will identify genetic changes that are associated with the risk for heart failure by using a new technology called whole genome sequencing (WGS). This will help us understand how heart failure happens and how we can diagnose it and treat it earlier.
We are seeking to understand: 1) the genetic basis for heart failure; 2) the challenges of implementing WGS for patients with heart diseases; 3) the best approach for improving medical care using genomic data.
What is WGS?
In the past, it was only possible to test one gene at a time. This is called single gene testing. For certain health conditions, single gene testing is still done, but it can take a long time and still may not provide an explanation. Today, one test can look for harmful variants in all of your genes at once. This test is called whole genome sequencing (WGS). Testing can take 4-6 months to complete. See our brochure for the four possible results of this test.
What should I know about genes and DNA?
Our bodies are made up of many cells, each of which contain our DNA. DNA is like an encyclopedia with instructions for how our body works. This information is structured into genes that are like the chapters in this book. There are about 25,000 genes in our cells most of which contain the instructions for making proteins.
Proteins are the functional and structural parts of a cell. The type of proteins made tell the cell what kind of cell it will be, such as a heart muscle cell, a brain cell, etc., and how that cell should act. Sometimes the DNA code can vary from person to person. These genetic variants help make each of us a unique individual. Genetic variants are usually harmless. Sometimes they affect minor things like hair colour but, occasionally, they can cause or put us at risk for serious health problems.
What are the benefits for families?
The WGS technology can capture much more information than those currently offered in the clinical diagnostic laboratory. We may be able to help you learn more about the heart condition in your family, including the risks to other family members and what screening or treatment may be appropriate.
What does the study involve?
Our study involves both your child and you since in genetics it is helpful to think in the context of the family. Here is what typically unfolds:
A) You will meet with the CGC team for a 60-90 minute research appointment. The study will be explained in detail and you will be asked for:
– consent for participation
– a detailed personal and family history
– a physical exam
– cardiac assessment of parents (echo, ECG)
– sample collection (bloodwork) if necessary
B) If consented your child (and in some cases you) will undergo whole genome sequencing (this part does not require any additional time on your end).
C) Once the WGS results are available, you will have a follow up appointment for 30-60 minutes with the CGC team +/- your SickKids cardiologist to review the results.
Are there any risks?
WGS may show changes in a gene that predicts a risk for a person to develop another genetic condition. These “additional findings” are unexpected and not related to why the testing was done in the first place. If one is found, other family members may need to be informed and offered testing, which can be upsetting and stressful for those involved.
Results of WGS testing will be stored in your child’s medical record. Therefore, these results will be available to your insurance company and may affect coverage and/or premiums (cost).
Who can I contact for more information?
Cardiac Genome Clinic Genetic Counsellor
Ted Rogers Centre for Heart Research
Clinical and Metabolic Genetics, SickKids
Tel: 416-813-7654 ext. 204862