Streamlined care for Canadians with mismatch repair deficient cancers through full-service genetic and epigenetic DNA sequencing


Human Health


Inherited mismatch repair (MMR) deficiency (also known as Lynch Syndrome, LS) affects at least 1 in 300 Canadians. It is a feature of families with heightened risk of colon, brain and gynaecological cancer. Despite a tenfold increased risk, the majority of LS patients are not well identified by the Canadian health system, which takes a piecemeal and overly complex approach to testing, including an excessive use of often-limited tumour tissues. As a result, the length of time to diagnosis is currently 1-3 years in Ontario and up to 6 years in other provinces. While they wait, many Canadians are developing advanced cancers. There is an urgent need for a more efficient, comprehensive MMR screening protocol to identify and treat high-risk patients earlier.

MMR tumours all display a biological feature (microsatellite instability, MSI) that leads to the accumulation of 10,000s of DNA mutations. The project aims to commercialize a MultiMMR tumour test previously developed by the researchers involved. In a single cost-efficient test, this comprehensive DNA sequencing method queries the MMR genes for germline and somatic mutations, MSI status and promoter methylation. MultiMMR conserves tissue, eliminates the need for serial molecular testing and helps differentiate LS from other hereditary cancers.

In partnership with the health solutions company Dynacare, the team will test and clinically validate the MultiMMR panel through a pilot study with various clinics nationally, and validate a new application of MultiMMR to blood cell-free DNA for proactive cancer screening in LS and constitutional mismatch repair deficiency (CMMRD) carriers. Within 3-5 years of completion, the project will reduce LS/CMMRD diagnosis time from 1-6 years to 4 months, saving 50-75% of patients from lifelong cancer screening. It will also reduce healthcare spending on molecular testing by more than 10%, and ultimately improve patient experiences and outcomes.