Link Found Between Hereditary Cancer Gene and Ancestor in Quebec

Recent research has unveiled significant insights into a hereditary cancer gene prevalent in Quebec's French-Canadian demographic. This discovery, stemming from a collaboration between McGill University and the Research Institute of the McGill University Health Centre, could potentially lead to more cost-effective screening processes for hereditary cancers.

The genetic variant in question is associated with Lynch syndrome, a condition that markedly heightens the risk of colorectal and other types of cancer. By analyzing genetic data from the CARTaGENE population cohort alongside genealogical information from the BALSAC database, researchers traced the origins of this variant to a single ancestor approximately 11 generations ago. The findings indicate that around one in every 800 French-Canadians carries this mutation, with elevated frequencies noted in specific regions such as Charlevoix, Côte-de-Beaupré, Saguenay-Lac-Saint-Jean, Beauce, and Côte-du-Sud.

Published in the journal Clinical Genetics, the study highlights the variant PMS2 c.2117del, which was first identified in 2008 within a single family affected by Lynch syndrome. The current research provides clarity on the widespread nature of this variant within the population and its historical roots.

According to the researchers, this study illustrates the significant interplay between clinical data and genetic history, emphasizing how historical records can enhance our understanding of present genetic risks. The senior researcher emphasized that such insights could revolutionize genetic screening processes in Quebec, making them more accessible and efficient.

Co-author Dr. William Foulkes pointed out that the commonality of this pathogenic variant suggests the possibility of developing a low-cost test that targets a limited number of variants. This approach could help identify individuals at high risk for up to 50% of inherited cancers. Early detection is crucial, especially in the case of colorectal cancer, which is often highly treatable when diagnosed early.

In conclusion, the findings from this study not only advance the understanding of hereditary cancer in Quebec but also pave the way for improved screening methodologies that could benefit many individuals at risk.