Some Teens More Genetically Predisposed to Become Heavy Smokers

Some teenagers appear to be more genetically predisposed than others to become heavy smokers, a new study suggests.

The researchers developed a genetic risk profile for heavy smokers. They then applied the findings to a study of 1,000 people from birth to age 38, to determine if there was a link between a high risk score and smoking patterns.

They found genetic risk score did not influence whether a person started to smoke. However, among people who did start to smoke, those with higher genetic risk were more likely to start smoking daily as teens, to become heavy smokers more quickly, to smoke heavily for a longer period, to develop nicotine dependence, to rely more on smoking to cope with stress and to have a harder time quitting, compared with people with a lower genetic risk.

Teens with a high genetic risk score who tried smoking were 24 percent more likely to smoke daily by age 15, and 43 percent more likely to smoke a pack a day by age 18, HealthDay reports. They were 27 percent more likely to become addicted to nicotine, and 22 percent more likely to fail their attempts at quitting smoking as adults.

Those with high risk genetic profiles smoked about 7,300 more cigarettes than the average smoker by the time they were 38, the researchers report in JAMA Psychiatry.

“The effects of genetic risk seem to be limited to people who start smoking as teens,” researcher Daniel Belsky of  Duke University’s Center for the Study of Aging and Human Development and the Duke Institute for Genome Sciences & Policy, said in a news release. “This suggests there may be something special about nicotine exposure in the adolescent brain, with respect to these genetic variants.”