DNA methylation can modify the function of a gene, determining whether or not the encoded protein is produced, and is an important mechanism by which the body regulates gene expression. Consequently, researchers have now examined the effects of smoking on DNA methylation.

Researchers measured the levels of DNA methylation in blood samples taken from nearly 16,000 volunteers, including a group of participants in the Framingham Heart Study that has been followed by researchers since 1971. DNA methylation sites across the human genome were compared between current smokers, former smokers and those who have never smoked.

The results showed that smoking resulted in DNA methylation of more than 7,000 genes, which is around a third of known human genes. The methylation levels of 1,405 genes were statistically significantly different among smokers compared with people who had never smoked.

Read more at www.news-medical.net