8 November, 2016
Smoking one pack of cigarettes a day could cause 150 extra genetic mutations in lung cells every year, according to new research.
The study, published in the journal Science, analysed the DNA sequence of cells from more than 5,000 cancers from both smokers and non-smokers.
Overall, the study found cancer cells from smokers tended to have a greater number of mutations within certain mutational signatures than non-smokers.
For example, most lung and throat cancers from smokers had many mutations in signature 4. The researchers went on to describe the other individual mutational signatures where they found differences for smokers versus non-smokers, including signatures 2, 5, 13 and 16. The researchers were able to estimate the number of mutations that would be caused in different types of cells.
The results support the theory that smoking causes cancer by increasing the number of mutations found in the cellular DNA, though the exact mechanism by which this happens isn’t completely clear.
Professor Sir Mike Stratton, joint lead author, said: “This study of smoking tells us that looking in the DNA of cancers can provide provocative new clues to how cancers develop and thus, potentially, how they can be prevented.”