Genetic Link to Smoking Addiction

Researchers have identified genetic variations that raise the risk of lung cancer for smokers and former smokers. The variants are common in the population - but they only raise lung cancer risk in those who have smoked.

And there is also some evidence to suggest that they may make carriers more addicted to tobacco. Current or former smokers who carry two copies of both variants, one from each parent - about 15% of the total - have a raised risk of 70-80%. Those who carry one copy of each variant have a raised risk of around 28%.