Scientists at the National Institute on Drug Abuse (NIDA) have identified genes that might increase a person's ability to quit smoking. This research was conducted by George Uhl at NIDA's Intramural Research Program and a team led by Jed Rose at the Center for Nicotine and Smoking Cessation Research at Duke University Medical Center.
"This research marks the first time we've been able to identify genes involved in the ability to quit smoking," says NIDA Director Nora Volkow. "It marks a movement from identifying the genetics of addiction vulnerability to identifying the genetic basis of successful abstinence. This knowledge could impact the success rate of cessation programs by helping health care providers choose the most appropriate treatment based on individual differences."
Uhl and his team screened the DNA of two groups of nicotine-dependent individuals, one that was able to successfully quit cigarette-smoking and one that was not.
"We identified 221 genes that distinguished successful quitters from those who were unsuccessful," said Uhl. "We know the functions of about 187 of these genes, but 34 have functions that are unknown at present. We also found that at least 62 of the genes that we had previously identified as playing roles in dependence to other drugs also contribute to nicotine dependence."
There are several gene variants that contribute both to success in quitting smoking and to vulnerability to become dependent on multiple substances. One gene is cadherin 13, a protein involved in cell adhesion, which determines how cells recognize and interact with their neighbors. Another is a cyclic G-dependent protein kinase gene, which plays a key role in normal brain development. These genes play specific roles in intracellular signaling and intercellular interactions, along with other genes involved in a variety of additional cellular processes. However, despite our current knowledge, more research is necessary to understand the precise mechanisms through which these genes may increase or reduce the rates of successful quitting.
"These findings provide ample justification for continuing the search for even more genetic variants associated with smoking cessation success," said Volkow. "We soon may be able to make use of this information to match treatments with the smokers most likely to benefit from them."
NIDA smoking fact sheet
This was an interesting story. I used to smoke and I had really nasty withdrawals.
Normally I'm a laid back and calm person, but when I couldn't smoke I had an explosive temper. People who knew me were shocked by how much I changed when I didn't smoke. It was like I was a different person.
I wonder if genetic differences were responsible for this.