Mayo Clinic: Common Gene Doubles Lung CA Risk, Even in Non-Smokers

MAYO CLINIC: COMMON GENE DOUBLES LUNG CA RISK, EVEN IN NON-SMOKERS

Mayo Clinic scientists have found that carrying a common gene doubles the risk of lung cancer, even in those who don’t use tobacco products. Their study appears in the May 26, 2008 issue of the Journal of the American Medical Association.

The Mayo team found that the gene that encodes for the alpha-1 antitrypsin could account for up to 12 percent of the lung cancer cases in the study population. They conclude further that the gene may be responsible for the same level of risk of the disease in the general population.

Normally the gene, labeled Ą1AT, produces a protein that stops enzymes from breaking down elastin, which keeps lung tissue elastic for normal function. Carriers of Ą1ATD commonly develop emphysema and/or chronic obstructive pulmonary disease (COPD). Prior to this study, the connection between Ą1ATD, COPD and lung cancer risk had not been established.

In the study, a team of Mayo researchers looked at three different groups: 1,443 patients with lung cancer treated at Mayo Clinic from 1997 to 2003; a control group of 797 residents in the community; and a second control group of 902 siblings of the lung cancer patients.

They found that among the patients who had lung cancer, the carrier rate for the gene was more than 13 percent, compared with the study participants in the control groups. Even if those with the gene had never smoked cigarettes, their risk of lung cancer was increases. Carrying the gene and smoking boosted risk by more than two times, they write.

Despite the study results, the researchers cautioned that cigarette smoking was the predominant risk for development of lung cancer.

Source: Mayo Clinic