Although tobacco use has decreased in many countries around the world, smoking remains the leading preventable cause of death. A new study published in the journal of the American Heart Association, Circulation: Cardiovascular Genetics, has concluded that smoking affects the human genome in the form of DNA methylation and that this impact can persist even 30 years after smoking cessation.
And is that cigarette smoking is an important modifier of DNA methylation. Experts have discovered genes associated with smoking that contribute to the development of diseases related to smoking , such as prostate cancer, stomach cancer, liver cancer, acute bronchitis or coronary heart disease.
The researchers analyzed blood samples from nearly 16,000 participants from 16 groups included in the CHARGE Consortium for Research on Heart and Aging in Genomic Epidemiology. , including a group from the Framingham Heart Study that researchers have followed since 1971.
Compared to nonsmokers, the scientists found that smoking-associated DNA methylation sites were associated with more than 7,000 genes, representing one-third of known human genes.
After 5 years without smoking, most cases of DNA methylation returned to normal, however, some remained even 30 years later, leaving a historical mark on the DNA of the participants.
“ Our study has found conclusive evidence that smoking has a lasting impact on our molecular machinery, an impact that can last for more than 30 years. The good news is that once you quit smoking, most DNA methylation signals return to normal levels (as if you’ve never smoked) after 5 years, which means your body is trying to heal itself. of the harmful effects of tobacco use ”, concludes Roby Joehanes, from Harvard Medical School and co-author of the work.
