AT Gene Deficiency Increases Lung Cancer Risk

Armen Hareyan's picture

A study links lung cancer to a certain gene variation - alpha1-antitrypsin gene deficiency, which increases the risk for developing lung cancer.

A team of researchers from Mayo Clinic examined 1856 lung cancer patients, 902 brothers and sisters with healthy lungs, and 1585 healthy people with matching age, gender, and ethnicity. All participants were asked for blood samples and the samples were checked for gene variations.

Researchers found that there are some forms of defective alpha1-antitrypsin gene (AT gene) leading to lung cancer development.


The blood sample test results showed that those with alpha1-AT gene deficiency are 100% more likely to develop lung cancer, even if they are non-smokers. Researchers suggest that because of this gene deficiency lung tissue is vulnerable to damage. Damaged lung tissue itself can create favorable conditions for cancer to develop.

The study also found a link between lung cancer, alpha1-AT gene and chronic obstructive pulmonary disease (COPD). People with two defective alpha1-AT gene variations are at high risk for developing COPD, and people with only one defective gene variation are at high risk for developing lung cancer. The results showed that COPD itself adds independent risk for lung cancer.

There are about 10 million Americans with alpha1-AT gene disorder, who are twice as likely to develop lung cancer, than those with normal gene variations. This means, that those with gene deficiency are still at high risk even if they don't smoke.

The study comes to explain why some non-smokers still suffer from lung cancer, while some smokers never suffer from the disease. However, the study makes it clear that smoking is still the number one cause of lung cancer.