How are genetics inovlved with nicotine addiction?

Some involvement: There are a group of genes that have been shown to predispose people to be more likely to develop nicotine addiction if they choose to smoke, and the absence of all these genes appears to be more likely in those who are able to "chip" occasionally - smoke a cigarette here and there "socially," - and yet not get addicted. For most people, 7 cigarettes in life will predict tobacco dependency.