Smoking changes your DNA

Scientists may have found a way for doctors to quantify a smoker's cancer risk. Tobacco use chemically modifies the activity of cancer genes, a new study shows.
Written by Janet Fang, Contributor

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

This post was originally published on Smartplanet.com

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