Tobacco is a major risk factor for lung cancer. The harmful substances contained in cigarettes favor the appearance of mutations in DNA. However, heavy smokers do not necessarily carry more mutations than others, according to a study published in Nature Genetics. How to explain this?
Although tobacco is responsible for most lung cancers, only a minority of smokers develop the disease. There are approximately 13 million smokers in France, for (nearly 90% due to tobacco) diagnosed each year. Researchers of thealbert College of Medicine suggest, in that some smokers have a system of La prévention repose sur l’évitement des perturbations négatives ou sur la réduction de leur…” data-image=”https://cdn.futura-sciences.com/buildsv6/images/midioriginal/0/7/0/070bdc60f3_50035320_amenagement-prevention-crue-clive-perrin-geograph-cc-2.jpg” data-url=”https://news.google.com/planete/definitions/developpement-durable-prevention-6509/” data-more=”Lire la suite”> mutations more robust than the others. explanations.
Monitoring of DNA mutations caused by tobacco
The specialists of Formation du cancer
La…” data-image=”https://cdn.futura-sciences.com/buildsv6/images/midioriginal/a/4/a/a4aa3c526e_50034154_cancer-du-poumon-cellules-anne-weston-lri-cruk-wellcome-images-filckr-nc-nd-02.jpg” data-url=”https://news.google.com/sante/definitions/medecine-cancer-108/” data-more=”Lire la suite”> Lung scientists have long suspected that cigarette smoke promotes cancer by causing mutations in the DNA of lung cells that, when accumulated over time, turn them into malignant cells. This claim remained difficult to prove due to technical limitations. ” But that could never be proven until this study, because there was no way to quantify the mutations in normal cells. says Jan Vijg, Ph.D., co-senior author of the study.
What the researchers lacked was the ability to sequence the entire genome of an isolated cell without the itself does not induce mutations that are then difficult to distinguish from the actual mutations caused by cigarette smoke. The technique that researchers atAlbert Einstein College of Medicine it has improved the SCMDA name. It was applied to the bronchial basal cells of 33 participants, aged 11 to 86 years, with varying degrees of smoking history. ” These lung cells can survive for years, even decades, and thus can accumulate mutations with age and smoking. »
the appearance and it is a normal process, but exposure to cigarette smoke, and its approximately 4,000 harmful substances, significantly increases the frequency of these phenomena. It seems clear that long-time smokers accumulate more mutations, which increases the risk of cancer. However, this is not what the scientists observed. ” The heaviest smokers did not have the highest number of mutations. Our data suggest that these individuals may have survived this long, despite heavy smoking, because they managed to prevent the accumulation of additional mutations.. »
This observation opens new avenues of research on the efficacy of DNA repair mechanisms. To date, it is difficult to estimate an individual’s DNA repair capacity, but scientists hope to develop a test that will make it possible. This could become a means of assessing each person’s risk of developing lung cancer in addition to already known parameters such as of smoking, the age of the first cigarette or the number of diaries