Original Title: Panels virtuels de gènes associés à l’épilepsie avec ou sans troubles neurodéveloppementaux analysés à partir du séquençage de nouvelle génération de l’exome : rapatriement d’une analyse réalisée hors Québec

Authors' objectives: The Ministère de la Santé et des Services sociaux (MSSS), in collaboration with the Réseau québécois de diagnostic moléculaire (RQDM), has initiated a comprehensive project to upgrade sequencing technology, and to develop and repatriate next-generation sequencing (NGS) tests performed outside of the province. At the MSSS’s request, the Institut national d'excellence en santé et en services sociaux (INESSS) is reviewing issues regarding the clinical, organizational and economic dimensions, and how best to implement these NGS tests from the perspective of Quebec’s healthcare system. This report specifically addresses virtual gene panels used to establish the molecular diagnosis of epilepsy with or without neurodevelopmental disorders.

Authors' results and conclusions: RESULTS (#1: POPULATIONAL DIMENSION): Epilepsy is a family of neurological brain disorders with heterogenous clinical presentations. In Quebec, approximately 1% of the population is believed to have epilepsy. Nearly 50% of children with epilepsy show a global developmental delay two years after the onset of the disease. It is estimated that 70 to 80% of epilepsy cases are attributable to a genetic cause. (#2: CLINICAL DIMENSION): The overall diagnostic yield of NGS, across all epileptic conditions, reportedly ranges from 18 to 24% for multigene panels (MGPs), 24 to 34% for WES, and 39 to 55% for whole genome sequencing (WGS). It should be noted that, at the time of writing this report, WGS was not available in clinical genetic practice in Quebec. (#3 ORGANIZATIONAL DIMENSION: In Quebec, there is an issue regarding the availability of professional resources in medical genetics and molecular biology laboratories. (#4 SOCIALCULTURAL DIMENSION): The implementation of genomic medicine raises ethical and legal issues, including the risk of genetic discrimination, the validity of consent, respect for confidentiality, and the protection of personal data and information. (#5 ECONOMIC DIMENSION): According to the budget impact analysis, repatriation genetic tests performed outside the province could generate savings of $321,200 ($289,000 to $354,000) if the tests were based on WES data, or savings of $68,000 ($61,000 to $75,000) if they were based on WGS. It should be noted that the costs of storing residual samples and of bioinformatics tools (licenses, data archiving) were not considered and will reduce the anticipated savings. CONCLUSION: The clinical algorithm proposed by an RQDM working group is consistent with recommendations from certain learned societies to perform genetic testing in individuals at high risk of epilepsy of genetic etiology. Such individuals have epileptic and developmental encephalopathy, infantile epileptic spasm syndromes, neurodevelopmental comorbidities, pharmacoresistance, and structural brain abnormalities, among others. This is also supported by data in the literature on the diagnostic yield of these tests in the context of epilepsy.

Project Status: Completed

Year Published: 2025

URL for published report: https://www.inesss.qc.ca/fileadmin/doc/INESSS/Rapports/Biologie_medicale/Panel_epilepsie_EC_INESSS.pdf

English language abstract: An English language summary is available

Publication Type: Other

Country: Canada

Province: Quebec

Organisation Name: Institut national d'excellence en sante et en services sociaux

Contact Address: L'Institut national d'excellence en sante et en services sociaux (INESSS) , 2021, avenue Union, bureau 10.083, Montreal, Quebec, Canada, H3A 2S9;Tel: 1+514-873-2563, Fax: 1+514-873-1369

Contact Name: demande@inesss.qc.ca

Contact Email: demande@inesss.qc.ca

Copyright: L'Institut national d'excellence en sante et en services sociaux (INESSS)