One expert thinks these studies alone cannot determine whether increased risk of lung cancer associated with gene variants on chromosome 15 is due to smoking or some other cause.
"Because there is such a powerful environmental effect of smoking on lung cancer, we can't say for certain whether the association in that part of the genome is related directly to smoking or to the cancer process itself or an interaction of the two," said Dr. Stephen J. Chanock, chief of the Laboratory of Translational Genomics at the U.S. National Cancer Institute and co-author of an accompanying Nature editorial.
Chanock thinks the increased risk for lung cancer results from interaction of smoking and the variants' role in cancer.
"This region is contributing to smoking behavior, and it may also contribute to the process that leads cells astray to develop cancer, particularly in the lungs," Chanock said. "The question is, which is it driving more, lung cancer or the smoking."
For more about lung cancer, visit the American Lung Association.
SOURCES: April 1, 2008, teleconference with: Kari Stefansson, M.D., president deCODE genetics Inc., Reykjavk, Iceland; Paul Brennan, Ph.D., International Agency for Research on Cancer, Lyon, France; Christopher Amos, Ph.D., M.D. Anderson Cancer Center, Houston; Stephen J. Chanock, M.D., chief, Laboratory of Translational Genomics, U.S. National Cancer Institute, Bethesda, Md.; April 3, 2008, Nature; April 2, 2008, online, Nature Genetics
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