Clusters of genetic variants can gauge the likelihood of success of two smoking cessation treatments, according to a study coauthored by two researchers at Brown University.
With the clinical foundation that many smokers respond better to some cessation treatments than others, the study charted the genetic variation within patients who used nicotine replacement therapy (NRT) and the medication bupropion (Zyban).
The study, supported by NIDA and the National Cancer Institute, was published in the June issue of the journal Archives of General Psychiatry. It can be viewed online.
“This is the first genome-wide study of the efficacy of bupropion and NRT for smoking cessation,” said Sean David of Brown University, the director of Memorial Hospital’s Primary Care Genetics Laboratory and Translational Research Center. “These results advance the field a step closer to the ultimate goal of personalized, genetically tailored medicine to help our patients quit smoking.”
The research team used a technique known as genome-wide association scans to compare DNA extracted from the blood of smokers who were either successful or unsuccessful in quitting using bupropion or such forms of NRT as a nicotine patch or nasal spray. Certain clusters of gene variants were present more frequently in the successful quitters among the 550 smokers who were successfully abstinent at all follow-up points of the study. (An additional 450 smokers were abstinent at some but not all points and thus were excluded from the final analyses.)
Interestingly, the variants in those who were successfully treated with bupropion were different from those who were helped by NRT. For example, a cluster of genes which regulates the body’s ability to process bupropion was associated with success on bupropion therapy, but not with success using NRT.
“These findings suggest that we may be able to improve the success rate for smoking cessation by using results of simple DNA tests,” said lead researcher George R. Uhl of Johns Hopkins University, the chief of NIDA's molecular neurobiology research branch.
Raymond Niaura, professor of psychiatry and human behavior, was the principal investigator for Brown’s component of the study. Caryn Lerman of the University of Pennsylvania and Jed Rose of Duke University also coauthored the study.