Scientists have identified another gene that might affect how vulnerable a person is to cigarette addiction. The finding may help researchers develop new ways to stop smoking.
Having a certain form of the gene makes it easier to kick the habit, or perhaps to avoid getting hooked in the first place, two studies suggest. But that apparent influence is modest."This is just one small piece of the puzzle" of what influences smoking behavior, said psychologist Caryn Lerman, an author of one of the studies.
Lerman is director of cancer genetics at the Lombardi Cancer Center of Georgetown University Medical Center in Washington. Her work appears in this month's issue of the journal Health Psychology.
It's at least the third gene to show evidence of an effect on smoking. Scientists hope that by understanding such biological influences, they can tailor treatments to particular smokers and get hints for finding better therapies.
Nicotine causes a surge of a substance called dopamine between certain brain cells. That feels good to the brain, so it encourages addiction. Brain cells use squirts of dopamine to communicate, and the gene in the new research tells brain cells how to make a structure called a transporter that mops the chemical up.
Lerman and colleagues theorize that it leads to a less efficient dopamine transporter, which leaves more dopamine between the brain cells. That might reduce a person's desire to pump up dopamine levels by using nicotine, they suggest.