Scientists smoke out genes behind lung cancer

By Ben Hirschler

LONDON (Reuters) - Scientists have found important genetic differences between people that may help explain why some smokers get lung cancer and others do not.

Three teams from France, Iceland and the United States said on Wednesday they had pinpointed a region of the genome containing genes that can put smokers at even greater risk of contracting the killer disease.

In all three studies, nicotine appears a major culprit.

The findings could eventually lead to better ways to prevent and treat lung cancer, the biggest cause of cancer-related death globally in men and the second most common in women.

"It opens the possibility that treatments that block these genes could be very beneficial as a treatment strategy against lung cancer, as well as against addiction," Paul Brennan of the International Agency for Research on Cancer in Lyon, France, told reporters.

Smoking causes nine out of 10 cases of lung cancer. Yet only about 15 percent of smokers actually develop the condition and doctors have long suspected that a genetic element is involved.

The new research confirms some smokers are indeed more vulnerable because of their DNA profile. Smokers with two copies of the genetic variations stand around a 23 percent risk of lung cancer, according to Brennan.

The findings mark another step in unraveling the genetic basis of diseases by analyzing common changes in the genetic code known as single nucleotide polymorphisms, or SNPs (pronounced "snips).