Rare Genetic Mutation Linked to High Lung Cancer Risk in Non-Smokers
- A rare inherited genetic mutation called EGFR T790M is associated with a twenty-five-fold increase in the risk of developing lung cancer, according to a study published in the...
- The association between the EGFR T790M mutation and lung cancer is even stronger among individuals who have never smoked.
- The EGFR gene encodes a receptor protein that governs critical cellular processes, including cell proliferation, survival, and differentiation.
A rare inherited genetic mutation called EGFR T790M is associated with a twenty-five-fold increase in the risk of developing lung cancer, according to a study published in the journal Science. Researchers from the Dana-Farber Cancer Institute and the 23andMe Research Institute analyzed anonymized genetic and medical data from more than 3.3 million participants to evaluate the impact of this rare germline variant.
Risk Levels Among Never-Smokers and Smokers
The association between the EGFR T790M mutation and lung cancer is even stronger among individuals who have never smoked. In this group, carriers of the variant faced a risk of developing lung cancer more than sixty times higher compared to non-carriers who did not smoke. Among participants with a history of smoking, carriers showed an increased risk of roughly ten times compared to non-carriers. Overall across the entire study population, the mutation was tied to a roughly twenty-five-fold rise in lung cancer risk.
Biological Function and Distinction From Somatic Mutations
The EGFR gene encodes a receptor protein that governs critical cellular processes, including cell proliferation, survival, and differentiation. Alterations within this gene frequently appear in lung cancer, particularly in pulmonary adenocarcinoma. Scientists emphasize the difference between somatic mutations, which arise strictly inside tumor cells over a person’s lifetime, and germline mutations, which exist from birth across all cells and can pass to offspring. While EGFR T790M is recognized in oncology as a somatic change linked to resistance against specific targeted anti-EGFR therapies, the Science study evaluated its presence as an inherited germline variant.
Implications for Genetic Screening and Future Monitoring
Initial indications linking EGFR T790M to hereditary lung cancer predisposition first surfaced in 2005 within a European family experiencing multiple lung cancer cases, followed by reports in other families with unusually high disease incidence. Because the variant is exceptionally rare, previous estimates of its exact risk were difficult to determine prior to analyzing a cohort exceeding three million people. Current medical screening protocols for lung cancer rely primarily on age and smoking history. The findings suggest that inherited genetic risk could eventually help identify individuals who might benefit from targeted monitoring via low-dose computed tomography, particularly people without a smoking history who typically remain outside standard screening criteria.