In the first study to analyze the impact of genetic factors on multiple stages of tobacco use in both men and women, a team of researchers from
Virginia Commonwealth University has found some of the strongest evidence yet for the role of genetic factors in smoking.
The multi-disciplinary team, from the Departments of Human Genetics and Psychiatry and VCU’s Massey Cancer Center, analyzed data from personal interviews with 6,805 male and female adult twins registered with the Mid-Atlantic Twin Registry at VCU.
The team found that people differed in their risk to try cigarettes at least once. The analysis indicated that 75 percent of those differences were accounted for by genetic factors. Similarly, genetic factors contributed to 80 percent of the risk that someone would become a regular tobacco user, which was defined as using an average of at least seven cigarettes per week for a minimum of four weeks, and 62 percent of the risk that they would become dependent upon nicotine.
The study, published early online by Psychological Medicine, found no difference between men and women in the role of genetic factors in the liability to try smoking, become a regular user of tobacco or become addicted to nicotine.
“Although many people try smoking, it’s been unclear why some people progress to regular tobacco use and then on to nicotine dependence,” says Dr. Hermine H. Maes, assistant professor of human genetics, a researcher at the VCU Institute of Psychiatric and Behavioral Genetics and lead author on the article. The study will be published in a print issue of Psychological Medicine later this year.
“Different studies have implicated genetic components in smoking initiation,” said Maes, who also is a member of the Cancer Control Program at VCU’s Massey Cancer Center. “But now we also can quantify the contributions of genetic factors, as well as the contributions of such environmental factors as others smoking at home, specific to regular tobacco use and to nicotine dependence.”