Certain Gene Found to Influence Why People Start Smoking and Why Some Get Addicted and Others Don't
WASHINGTON - Quitting smoking can be difficult for some and almost impossible for others. The reason -- your genes -- New research has found that a certain gene can make the difference as to whether or not someone will start smoking and then become addicted to the nicotine. In two studies featured in this month's American Psychological Association's journal of Health Psychology, researchers discovered that people carrying a particular version of the dopamine transporter gene (SLC6A3-9) are less likely to start smoking before the age of 16 and are more likely to be able to quit smoking if they start.
In their article, "Evidence Suggesting the Role of Specific Genetic Factors in Cigarette Smoking," psychologist Caryn Lerman, Ph.D., of the Georgetown University Medical Center and her co-authors demonstrated for the first time that a link exists between smoking behavior and the dopamine transporter gene (SLC6A3-9). In their study of 289 smokers and 233 nonsmokers, they found that individuals with an SLC6A3-9 genotype were less likely to be smokers than individuals without that gene. Furthermore, those with that gene started smoking later and were able to quit for longer periods of time than other smokers.
Although many smokers attempt to quit at some point in their lives, only 20 percent actually succeed in quitting, say researchers. In their article, "A Genetic Association for Cigarette Smoking Behavior," Dean H. Hamer, Ph.D., of the National Cancer Institute and colleagues found from examining 1,107 nonsmokers, current smokers and former smokers that the SLC6A3-9 gene was associated with certain personality characteristics that influenced a person's susceptibility of being able to start and stop smoking.
A person with the SLC6A3-9 genotype was found to have lower novelty seeking traits than a person without this genotype, according to the study. And because novelty seeking has been associated with a desire to smoke, said Dr. Hamer, "a low level of novelty seeking could be a predictor of smoking cessation. Indeed, average novelty seeking scores were found to be significantly lower in former smokers than in current smokers. Those with low levels of novelty seeking have an easier time giving up cigarettes than those with high levels of novelty seeking."
"We found that individuals who have the SLC6A3-9 gene were one and a half times more likely to have quit smoking than individuals lacking this gene," said Dr. Hamer. "However," he cautioned that, "the SLC6A3-9 gene is not a strict determinant of the ability to quit smoking, but rather an influence on an individual's general need and responsiveness to external stimuli, of which cigarette smoking is but one example. Hopefully, with more of an understanding of the genetics of cigarette smoking behavior, we can develop more effective, targeted pharmacological and psychoeducational cessation strategies that will take these individual differences into account."
Articles:
"Evidence Suggesting the Role of Specific Genetic Factors in
Cigarette Smoking," Caryn Lerman, Ph.D., Janet Audrain, Ph.D., and David
Main, M.S., Georgetown University Medical Center, Neal R. Boyd, Ph.D., Fox
Chase Cancer, Neil E. Caporaso, M.D., Elise D. Bowman, M.S., Benjamin
Lockshin, M.D., Peter G. Shields, M.D., National Cancer Institute, Health
Psychology, Vol 18, No. 1.
"A Genetic Association for Cigarette Smoking Behavior," Dean H. Hamer,
Ph.D., Sue Z. Sabol, Ph.D., Mark L. Nelson, Ph.D., Craig Fisher, Ph.D.,
Lorraine Gunzerath, Ph.D., Cindy L. Brody, M.S., Stella Hu, M.S., and Leo
A. Sirota, Ph.D., National Cancer Institute, Benjamin D. Greenberg, M.D.,
Frank R. Lucas IV, B.S., Jonathan Benjamin, M.D., Dennis L. Murphy, M.D.,
National Institute of Mental Health, Stephen E. Marcus, Ph.D., National
Institute of Dental Research, Health Psychology, Vol 18, No.1.
(Full Text available from the APA Public Affairs Office or at www.apa.org/journals/hea.html)
Caryn Lerman, Ph.D., can be reached at 202-687-0806 or at lermanc@gunet.georgetown.edu and Dean H. Hamer, M.D., can be reached at 301-402-2709 or at deanh@helix.nih.gov
The American Psychological Association (APA), in Washington, DC, is the largest scientific and professional organization representing psychology in the United States and is the world's largest association of psychologists. APA's membership includes more than 155,000 researchers, educators, clinicians, consultants and students. Through its divisions in 50 subfields of psychology and affiliations with 58 state, territorial and Canadian provincial associations, APA works to advance psychology as a science, as a profession and as a means of promoting human welfare.
Journal
Health Psychology