Smoking: 600 genetic mutations of lung cells per year

Smoking remains the leading cause of cancer worldwide, with more than one million people affected by lung cancer each year. A study published in Nature shows that this carcinogenic action is linked to the accumulation of an impressive number of mutations following prolonged exposure to cigarette smoke. In this tobacco-free month of November, you might as well have this clear information in mind to convince yourself to quit smoking.

With more than one billion smokers worldwide, cigarettes still represent the main risk factor for premature mortality today.

Among the many harmful effects associated with smoking, such as the increased risk of heart disease and lung disease, the increased risk of cancer remains without a doubt the main consequence of this bad habit: smokers have a 20 times greater risk of be affected by lung cancer than non-smokers.

Globally, it is estimated that more than 500 million people will die over the next few years from illnesses directly caused by smoking.

About sixty mutagenic substances

Our genetic material is undoubtedly the most precious thing we have: it is thanks to our genes that we produce all the proteins that make up our body and that allow us to live in good health. If cigarettes are so harmful to health, it is precisely because tobacco smoke contains around sixty compounds which have the capacity to modify these genes, we speak of a mutagenic substance, and to cause the production of defective proteins, incapable to perform their duties properly. When these modifications, called mutations, affect a gene involved in the production of a protein essential to the control of cell growth, these cells adopt abnormal behavior that can ultimately lead to the development of cancer.

Smoking: One genetic mutation every 15 cigarettes

To determine the extent of the damage caused by cigarette smoke, British researchers undertook the daunting task of determining all the mutations present in cancer cells from the lung of a smoker. Thanks to new DNA sequencing technologies, researchers have succeeded in demonstrating that these cancer cells contain no less than 22,910 distinct mutations, illustrating how the combined presence of several carcinogens can wreak havoc in the genetic material of smokers. . Even if a large part of these mutations are said to be “silent”, that is to say that they do not affect regions of the DNA which participate in the control of cellular functions (the genes that code them), the researchers nevertheless observed a large number of mutations in important genes that play a crucial role in cell growth, including p53 and Rb. The carcinogenic potential of cigarette smoke is so high that researchers estimate that on average it causes one genetic mutation every 15 cigarettes, or almost two mutations per pack. In other words, a person who regularly smokes a pack of cigarettes a day will accumulate almost 600 mutations in the genetic material of their lung cells each year.

Psssssst :  Empathy Decreases Pain Sensation: 4 Unlikely Experiments Demonstrate It

Quitting smoking causes the replacement of damaged cells

In light of these observations, we understand better why cigarettes are so harmful to the health of smokers. But all is not lost for people who want to quit smoking: cells containing genetic mutations are gradually replaced by healthy cells containing no mutations following smoking cessation, so that the risk of cancer of the lung become similar to those of a non-smoker 15 years later.

To help quit smoking, don’t hesitate to get help: https://www.tabac-info-service.fr


Pleasance et al. A small-cell lung cancer genome with complex signatures of tobacco exposure. Nature, 463:184-90.

Read also:

Leukemia: vitamin C prevents and fights it


Back to top button

Adblock Detected

Please disable your ad blocker to be able to view the page content. For an independent site with free content, it's literally a matter of life and death to have ads. Thank you for your understanding! Thanks