As researchers continue to assail the notion of free will, one study finds that genetics - rather than plain-old willpower - might explain why some people cannot stop smoking.
Researchers in New Zealand followed1,000 people from birth to age 38 to find genetic markers for an increased risk of tobacco addiction. They found genetic markers that identified those with a propensity to begin smoking and soon progress to a pack-a-day habit. In adulthood, these people found greater difficulty breaking that habit than did others without the genetic markers.
Researchers reported the findings in the journal JAMA Psychiatry today.
In analyzing DNA samples from 880 men and women of European decent, researchers found that people with high-risk markers were 27 percent more likely to smoke heavily and 22 percent more apt to fail attempts to quit.
"Genetic risk accelerated the development of smoking behaviour," said Dr. Daniel Belsky, lead investigator for the study, with Duke University. "Teens at a high genetic risk transitioned quickly from trying cigarettes to becoming regular, heavy smokers."
He added, "This suggests there may be something special about nicotine exposure in the adolescent brain, with respect to these genetic variants."
Denise Kandel, a professor at Columbia University who was not involved with the research, said the study marked adolescence as a time of particularly high risk for tobacco addiction. "The results illustrate why adolescence is of crucial importance for the development and targeting of prevention and intervention efforts," she said. "How this genetic risk affects brain functions, which in turn affect reactions to nicotine, remains to be determined."
The newfound knowledge, however, wouldn't be enough to allow public health officials to develop a screening tool for those most at risk of developing addiction.
"Public health policies that make it harder for teens to become regular smokers should continue to be a focus in anti-smoking efforts," said Belsky.