Professor RP Young (Associate Professor of Medicine and Molecular Medicine, School of Biological Sciences, University of Auckland) and his team have developed a reliable genetic test "Respiragene" based on 20 single nucleotide polymorphisms that can be used (together with details of personal and family history) to calculate a smoker's lifetime risk of developing lung cancer. The expectation is that whatever the score (estimated lifetime risk will vary from 5% to 50%) the result will counter "optimism bias" of the smoker and encourage smoking cessation and this assumption is supported by previous research on similar tests and smoking cessation. The investigators plan to recruit two groups of subjects for smoking cessation but only one group will have the Respiragene test. Eight weekly smoking cessation sessions will be carried out at a Surrey primary care medical centre and will follow the usual format for National Health Service smoking cessation clinics using Champix (varenicline), counselling and the carbon monoxide breath meter but with added: evaluation questionnaires, fagerstrom nicotine addiction score, salivary cotinine (metabolite of nicotine) test. The main outcome measures will be estimation of smoking cessation at 4 weeks and six months after the completion of the seven smoking cessation sessions. Successful smoking cessation has to be confirmed by negative salivary cotinine at 4 weeks and six months and questionnaires will be used to estimate the influence of the Respiragene test compared with standard procedures such as counselling and the carbon monoxide breath readings.