Nicotine metabolism makes smokers crave.

• Position: Lung Function - Brief article

New genetic markers associated with a fast rate of nicotine metabolism, which potentially leads individuals to smoke more, thereby increasing their risk for lung cancer, have been discovered by researchers at the University of Hawaii, Honolulu.

Loi'c Le Marchand, professor in the Cancer Center's Epidemiology Program, and his colleagues identified differences in the CYP2A6 gene that are associated with a high rate of nicotine metabolism. Smokers who have these CYP2A6 markers may smoke more cigarettes or inhale a greater amount of nicotine per cigarette than smokers who metabolize nicotine less rapidly in order to maintain stable levels of nicotine in the blood.

"Smokers adjust the way they smoke to satisfy their craving for nicotine, which is the highly addictive component in cigarettes that makes people want to smoke. 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," says Le Marchand.

Adds Randall F. Holcombe, director of the Cancer Center...