MEDICAL RESEARCH Study: Trait increases chance of lung cancer

The report is 'the hardest first step,' a geneticist said.
CINCINNATI (AP) -- Medical researchers have located a genetic indicator of a higher than normal risk of developing lung cancer, a discovery that might help identify those most susceptible to the disease.
"This is a big development," said Janet Healy, executive director of the Alliance for Lung Cancer Advocacy Support and Education, based in Vancouver, Wash. "So many people say that if we can just get people to stop smoking, all the questions about lung cancer would be answered. This study shows that there's more going on than we assumed."
Researchers at the University of Cincinnati led a wide-ranging investigation for the National Cancer Institute, which funded the five-year, $5.9 million project involving a consortium of medical centers and federal health agencies.
The full study has been posted on the Web site of the American Journal of Human Genetics and will be published in the journal's September edition.
In the study
The results are based on data from families with multiple cases of lung cancer among blood relatives. After starting with more than 26,000 people with lung cancer, 3,500 families were identified as having more than one case of lung cancer among blood relatives.
Researchers have been able to complete detailed genetic analysis of 52 of those families for the study.
"When we started out, a lot of people didn't believe lung cancer would have this kind of gene. By finding these families, we have shown that it does," said Marshall Anderson, the study's principal investigator and a University of Cincinnati professor of environmental health.
Anderson and co-investigator Susan Pinney, an epidemiologist with UC's department of environmental health, coordinated the work of more than 20 researchers scattered nationwide.
The researchers' report concludes that families with multiple cases of lung cancer share an inherited genetic trait that can make it harder for their bodies to stop tumor growth.
Researchers traced the common trait to an area of just 50 genes located along chromosome 6, one of the body's 22 pairs of chromosomes. People carrying this trait could be more vulnerable to harm caused by smoking, and they could pass the trait on to their children, Anderson and Pinney said.
"Narrowing it down that much is the hardest first step," said Dr. Ranjan Deka, a geneticist at UC who is studying diabetes and obesity. "To identify even a region of genes in a disease as complex as lung cancer is a very challenging task."
Work remains
Much work remains, and there still isn't a test people can take to find out whether they have the gene. But it could be an important step toward developing better treatments.
"Unfortunately, the mortality rate for lung cancer hasn't changed very much since I started in medicine 25 years ago. Now we have an opportunity to make some meaningful clinical progress," said Dr. William Martin, dean of the UC College of Medicine.