Smokers who carry the breast cancer gene BRCA2 face "enormously" increased odds of developing lung cancer, a new study suggests.
The findings, published in the journal
Nature, were based on a comparison of the genetic codes of 27,000 people. The results indicated the gene could double the likelihood of getting lung cancer,
BBC News reports.
"It is a massive increase in the risk of developing lung cancer," said researcher Richard Houlston, with the Institute of Cancer Research in London. "There is a subset of the population who are at very significant risk. The most important thing is reducing smoking; it is so bad for other diseases, as well as [increasing] the risk of lung cancer."
The BRCA gene has been conclusively linked to breast cancer, but also with other forms of the disease, such as ovarian cancer and prostate cancer. Mutations to the BRCA genes stop DNA from repairing itself effectively.
Smokers have 40 times the chance of developing lung cancer, but the new research showed those with a BRCA2 mutation were nearly 80 times more likely to develop the usually fatal disease, the analysis showed.
A quarter of those carrying the mutation, and who also smoke, will develop lung cancer, the research team said.
Cancer Research UK suggested the discovery could mean treatments being developed for breast cancer may also work in some cases of lung cancer.
"We've known for two decades that inherited mutations in BRCA2 made people more likely to develop breast and ovarian cancer, but these new findings show a greater risk of lung cancer too, especially for people who smoke," said Peter Johnson, Cancer Research UK's chief clinician.
"Importantly this research suggests that treatments designed for breast and ovarian cancer may also be effective in lung cancer, where we urgently need new drugs."