Smoking leaves footprint on human DNA

A new research says that smoking leaves its impression on the human genome in the form of DNA methylation, a process by which cells control gene activity, reports ANI.

The new findings suggest that DNA methylation could be an important sign that reveals an individual's smoking history and could provide researchers with potential targets for new 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," said author Stephanie J. London, adding, "Equally important is our finding that even after someone stops smoking, we still see the effects of smoking on their DNA."

Smoking remains the leading preventable cause of death worldwide, despite a decline in smoking in many countries as a result of smoking cessation campaigns and legislative action. Even decades after stopping, former smokers are at longterm risk of developing diseases including some cancers, chronic obstructive pulmonary disease, and stroke.

While the molecular mechanisms responsible for these long-term effects remain poorly understood, previous studies linking DNA methylation sites to genes involved with coronary heart disease and pulmonary disease suggest it may play an important role.

Researchers conducted a meta-analysis of DNA methylation sites across the human genome using blood samples taken from nearly 16,000 participants from 16 groups of the Cohorts for Heart and Aging Research in Genetic Epidemiology (CHARGE) Consortium, including a group of the Framingham Heart Study that has been followed by researchers since 1971. The researchers compared DNA methylation sites in current and former smokers to those who never smoked.