The answer to why some smokers can quit and others can’t lies partly in their genes. Researchers now are harnessing information that provides information about a smoker’s genetic risk for nicotine dependence which ultimately may lead to a tailored approach to quitting.
The University of Nebraska Medical Center College of Nursing received a $40,000 grant to study whether receiving personalized genetic information on nicotine addiction will influence smokers’ attitude towards smoking and quitting.
Funded by Nebraska Legislative Bill 506, also referred to as the Health Care Cash Fund and tobacco settlement funds, the grant focuses on reducing cancer and smoking-related heart disease.
Researchers will study one variant, rs1051730, on the CHRNA3 gene, which affects dopamine production and signals the brain’s reward or pleasure pathways. This variant correlates with nicotine dependence and the amount of cigarettes smoked, said Julia Houfek, PhD, professor, UNMC College of Nursing and lead researcher of the study.
Ninety smokers, age 19 and older who smoke at least 10 cigarettes a day, will be enrolled in the study. For comparison, half of the participants will receive information about their personal genetic profile during the study. Once the study is complete, the other group will receive their genetic information.
There are three variations on the gene that influence nicotine addiction: CC, CT and TT. Those with CC and CT are less likely to become nicotine dependent as those with TT.
The goal of the study is to find out how study participants will interpret the genetic information they receive and how they think about their smoking. The study is not a smoking cessation study, and there is no requirement to try to quit. Researchers will follow people after the study is completed to see if they seek out help to quit smoking.
“We know that smoking cessation treatments are not a one-size fits all solution,” Dr. Houfek said. “What may work for one person may not work for another. We want to learn how people interpret this information and see if the genetics information affects behavior.
“It’s estimated about 40 to 70 percent of smoking behavior is influenced by genes. We are harnessing this new technology that enables the identification of specific genes that influence someone to take up the habit and continue smoking.”
She said understanding the genetic contributions to smoking and the genotypes that influence cessation is rapidly progressing, and it is anticipated that genetically-informed smoking cessation will be developed in the near future.
“It may be that if someone is more addicted that both medication and behavioral therapy is needed to help them quit,” Dr. Houfek said. “Some may be more motivated to use several methods in order to quit.”
She said results of the study will contribute to the body of scientific knowledge. In the future, this may be important in tailoring smoking cessation programs to the appropriate type and dose and behavioral therapy.
“Even with cessation treatment guidelines, there’s little guidance to best match smokers with the most effective medication and behavioral therapy,” Dr. Houfek said. “Currently the recommendations are based on personal preference or availability. By knowing how the variations in DNA affect smokers’ responses to the medications, we will be better able to match them with the best treatment.”
Cigarette smoking continues to be a major contributor of death, disability and economic burden. In 2010, almost 70 percent of smokers wanted to quit but only 52 percent quit for at least one day and only 6 percent reported quitting success.
Source: University of Nebraska Medical Center