For immediate release – August 17, 2011 (Toronto) – Smokers with variations in two specific genes have a greater risk of smoking more cigarettes, becoming more dependent on nicotine and developing lung cancer, a new study from the Centre for Addiction and Mental Health (CAMH) shows.

The cancer risk from these two genes appears to be even higher in smokers who consume 20 or fewer cigarettes a day, according to the study published in the September issue of the Journal of the National Cancer Institute.

CAMH Scientist Dr. Rachel Tyndale and her team studied two genes: the nicotine metabolic gene (CYP2A6) and the nicotinic gene cluster (CHRNA5-A3-B3). These genes have been independently linked to smoking behaviours and lung cancer.