"This variant plays essentially no role in whether an individual initiates smoking or not, which is strongly driven by environmental factors. However, if a person with the high-risk does begin smoking, they will smoke a higher number of s per day, have a higher intensity of smoking, and have a higher age of smoking cessation than those with the low-risk variant, increasing their risk for . The problem with smoking cessation pharmacotherapy using is that it works modestly, at best, and the vast majority of smoking cessation is done without any medication. However, data suggest that people with the high-risk variant rs16969968 have the greatest difficulty quitting and stand to benefit the most from medication, although the evidence is still controversial. This makes sense since this variant affects function. Improved implementation of pharmacotherapy, using patients’ genetics as a guide, could have a huge impact."