Tobacco smoking is a persistent global public health problem that is responsible for over 5 million deaths annually.1, 2 Because there are clear health benefits of quitting smoking irrespective of smoking history, current age, or presence of smoking-induced diseases,1–3 efforts to promote smoking cessation are a high public health priority. More than 95 percent of smoking quit attempts fail within one year,4 and symptoms of nicotine withdrawal (NicW) are a major precipitating factor for relapse.5, 6 It has been argued that the severity of NicW symptoms, rather than the number of cigarettes smoked or the severity of nicotine dependence, best predicts the outcome of smoking cessation attempts.7 Thus, understanding the genetics of NicW could help to improve tobacco smoking cessation treatment efforts and significantly reduce the harm caused by smoking.
