Date Published: 12 September 2008
Genetic region linked to fivefold increased lung cancer risk
People who have a family history of lung cancer and genetic variations in a particular region of DNA are more than five times more likely to develop lung cancer than other people, US scientists have found.
Researchers at Washington University School of Medicine in St. Louis, Missouri, have found that a narrow region on chromosome 15 contains genetic variations that are strongly associated with lung cancer in people with a family history of the disease, regardless of whether or not the individuals are smokers.
This region of DNA has now been implicated in the development of lung cancer in a number of studies, raising hopes that a genetic test could be used to alert people to their high risk.
"If we can identify the genetic factors linked to lung cancer in such people before they get the disease, we can take steps to help prevent it." Dr Ming You, Siteman Cancer Centre, Washington University.
Senior author Dr Ming You, of the university's Siteman Cancer Centre, noted that many smokers do not get lung cancer, suggesting that genetics are also involved.
"We also know that some families have a high incidence of lung cancer," he continued. "If we can identify the genetic factors linked to lung cancer in such people before they get the disease, we can take steps to help prevent it. This genetic region might be part of the answer."
The researchers compared DNA samples of 194 Caucasian people with a strong family history of lung cancer with those of 219 similar people over the age of 60 with no history of the disease.
Their DNA was screened for more than 300,000 known genetic variations and the researchers identified several which were strongly associated with inherited lung cancer, with the most strongly linked appearing on chromosome 15.
These genetic variants were much more common in people with lung cancer than with people who were cancer-free.
Dr You said that the findings, which appear in the Journal of the National Cancer Institute, may be "very important information".
"It would suggest that specific genes in this region and smoking are independent risk factors for lung cancer, and together they might cause an even greater increase in lung cancer risk."
Dr You added:
"These genes play roles in cellular proliferation and cell death. And they are active in lung cancer tumours. More research will be needed to fully delineate the part they play in lung cancer and whether they will be good targets for cancer therapies in the future."