Smoking scars DNA, research suggests
The smoking “footprint” is left on the DNA methylation, which is a process where cells control gene activity. This means that DNA methylation may have important clues about a person’s smoking history, allowing researchers to have more targets for developing novel therapies.
“These results are important because methylation, as one of the mechanisms of the regulation of gene expression, affects what genes are turned on, which has implications for the development of smoking-related diseases,” Dr. Stephanie London, last author and deputy chief of the Epidemiology Branch at the National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, North Carolina, said. “Equally important is our finding that even after someone stops smoking, we still see the effects of smoking on their DNA.”
Smoking continues to be the top preventable cause of death around the world, even though smoking rates have declined in many nations. Experts attribute these improvements to smoking cessation campaigns as well as legislative action. Unfortunately, even after smokers have stopped smoking for decades, they continue to be at risk for serious diseases like stroke and cancer.
“Our study has found compelling evidence that smoking has a long-lasting impact on our molecular machinery, an impact that can last more than 30 years,” Dr. Roby Joehanes of Hebrew SeniorLife, first author and an instructor at Harvard Medical School, said. “The encouraging news is that once you stop smoking, the majority of DNA methylation signals return to never-smoker levels after five years, which means your body is trying to heal itself of the harmful impacts of tobacco smoking.”
Organizations in this story
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National Institutes of Health 9000 Rockville Pike Bethesda, MD - 20892