A common gene mutation doubles the risk of lung cancer, according to researchers at the Mayo Clinic.
The genetic disorder is called Alpha-one antitrypsin deficiency. It causes lung tissue to lose elasticity.
The disorder is often found in people who have chronic bronchitis or emphysema. Doctor Ping Yang led the research. She says smokers with the gene mutation are a thousand percent more likely to develop lung cancer.
"I just do not want to mislead the public that if they do not carry the gene they have a pass for being a smoker," she said. "That's absolutely not right."
She said smoking causes 90 percent of all lung cancers, but this disorder increases the chances of lung cancer for smokers and non-smokers alike.
"That means a smoker, a heavy smoker, can have 500-percent increased risk or even higher to develop lung cancer," Yang said. "The gene effect I found was only that double on top of these risk factors."
That means a heavy smoker's risk of developing lung cancer increases to 1,000 percent. Someone who has has never been exposed to cigarette smoke, but carries the genetic disorder would have a tiny risk.
Yang suggests getting tested for the gene if your family has a history of chronic pulmonary diseases.