Smokers with particular genetic markers may have higher nicotine metabolisms, increasing how much they smoke and, consequently, the risk of lung cancer.
Scientists in Hawaii identified differences in the CYP2A6 gene that are linked to a high rate of nicotine metabolism.
People with higher nicotine metabolisms are more likely to smoke more cigarettes and/or inhale more nicotine per cigarette than those without.
Dr. Loïc Le Marchand, a professor in the UH Cancer Center’s Epidemiology Program, said:
“Smokers with the genetic markers we discovered, smoke more extensively in order to keep their nicotine levels high and achieve the desired effects of nicotine in the brain.”
Dr. Randall F. Holcombe, director of the UH Cancer Center, added: “This new finding could identify smokers who are at greater risk for lung cancer.”
The scientists hope to use the knowledge of the markers to help doctors and public health leaders improve cancer prevention strategies.
“Application of this research may improve the survival and quality of life of lung cancer patients, since continued use of tobacco products after diagnosis is known to correlate with poor outcomes,” Holocombe said.
In a statement, a spokesperson said: “Smokers identified as being at high risk for the disease could be offered regular screenings by low-dose CT scans.”
People with the markers linked to a high nicotine metabolism are likely to experience greater exposure to tobacco-derived carcinogens, the study found.
Scientists analysed data from the UH Cancer Center’s Multiethnic Cohort Study (MEC) of 2,239 smokers.
Le Marchand said: “We were able to translate differences in lung cancer risk that we first observed among Hawai’i’s ethnic groups into information that has implications for the occurrence and prevention of a common and very deadly cancer.”
The US Centers for Disease Control and Prevention website states: “People who smoke cigarettes are 15 to 30 times more likely to get lung cancer or die from lung cancer than people who do not smoke.”