Those were the findings of a prospective study conducted in 281 7th grade students from 10 schools in Canada who had begun to smoke but were not yet addicted. Participants were followed for, on average, 29.9 months; they completed questionnaires about their smoking every three or four months during the school year, and provided blood samples. During follow-up from time of first inhalation, 29% of the youngsters became dependent on nicotine. Subjects with the genetic variant that caused slowed inactivation of nicotine were almost three times more likely to develop tobacco dependence (O'Loughlin J et al: 

: Another example of how genetic screening may change pediatric practice! One day, we may target counseling based on how likely a patient is to develop a disease or, as in this case, an addiction.