1.   The findings provide the first scientific evidence that drug dependency, including cigarette addiction, is not just a lack of willpower.

2.   The first surprise, to researchers at least, is how variable cigarette addiction can be.

3.   When he became interested in the metabolic basis of cigarette addiction, Schachter persuaded friends near his summer home in East Hampton to join a study.

4.   Novelty-seeking might promote cigarette addiction, so scoring lower on this trait might also be protective, they said.

5.   Scientists have identified another gene that might affect how vulnerable a person is to cigarette addiction.