Genetics may play a role in lung cancer

Lung cancer appears to run in families, researchers have found, though exposure to tobacco smoke is still the dominant cause of the disease even for those who may be genetically predisposed.

The strongest family link was found in the relatives of patients who developed the disease at age 60 or younger.

The parents of such people had nearly a 3 1/2 times higher risk of also developing the disease compared to the general population, the study said.

For siblings in such cases, the risk was more than three times higher and for children slightly less than that.

Researchers at Landspitali University Hospital in Reykjavik, Iceland, traced the genetic links by looking at all 2,756 patients diagnosed with lung cancer in the country from 1955 to 2002 and linking them with an extensive genealogical database containing all living Icelanders and most of their ancestors since the settlement of the country.

The study was published in the Dec. 22 issue of the Journal of the American Medical Assn.