Genome-wide Sequencing Ontario: A clinical collaboration for rare disease diagnostics (GSO) is a partnership between The Hospital for Sick Children (SickKids) and CHEO. GSO provides Ministry of Health (MOH) funded clinical genome-wide sequencing in Ontario.

The first phase of GSO was a two-year pilot completed between the period of April 2021 to 2023. The GSO pilot built capacity to deliver clinical-grade GWS to Ontario patients suspected of having a genetic condition. This resulted in continued funding of clinical exome sequencing by the Ontario MOH. The outcomes of this first pilot, as well as the current work of GSO, will continue to inform the MOH’s decisions on the evolution of a clinical GWS service in Ontario and the establishment of this service in Ontario long-term.

Genome-Wide Sequencing

Genome-wide sequencing (GWS) includes whole exome (WES) and whole genome sequencing (WGS). This type of analysis provides broad detection and evaluation of genetic variants. WES and WGS are currently the most comprehensive genetic tests available and are used to identify underlying genetic causes for conditions where traditional approaches have failed to find a diagnosis.

GWS can be offered to eligible patients suspected of having a genetic disorder. Obtaining a genetic diagnosis can improve patient health and family well-being by enabling informed care/treatment, providing emotional relief and closure, allowing for accurate recurrence risk counselling, and ending a diagnostic odyssey.