The Bulletin

Smoking changes your DNA

Posting in Cancer

Tobacco use can chemically modify and affect the activity of genes known to increase the risk of developing cancer. ScienceNOW reports.

We’re not talking about altering your genetic code. Rather, it’s about so-called epigenetic modifications – when chemical compounds bind to DNA molecules, turning genes on and off. (These can influence traits ranging from obesity to sexual preference.)

This is the first study to establish a close link between epigenetic modifications on a cancer gene and the risk of developing the disease.

Specific epigenetic patterns on the genes of smokers have been identified before, but because those modified genes don’t have a direct link to cancer, it’s been unclear whether these chemical alterations increase the risk of developing the disease.

Now, researchers led by James Flanagan from Imperial College London analyzed epigenetic signatures in blood cells from 374 individuals enrolled in a massive study called the European Prospective Investigation into Cancer and Nutrition (EPIC).

  • Compared with people who had never smoked, smokers have fewer chemical tags called methyl groups on 20 different regions of their DNA.
  • The team then narrowed down the epigenetic modifications to several sites located in four genes that have been linked to cancer before.

It's unclear why increasing the activity of the genes would cause cancer, but we do know that individuals who don't have cancer don’t usually have these modifications.

Researchers hope the work will make it possible for doctors to quantify your cancer risk simply through an epigenetic analysis of your DNA.

The work was published in Human Molecular Genetics.

[Via ScienceNOW]

Image by b0r0da via Flickr

— By on December 21, 2012, 2:47 PM PST

Janet Fang

Contributing Editor

Janet Fang has written for Nature, Discover and the Point Reyes Light. She is currently a lab technician at Lamont-Doherty Earth Observatory. She holds degrees from the University of California, Berkeley and Columbia University. She is based in New York. Follow her on Twitter. Disclosure