Despite comparable estimates of 'heritability' for tobacco smoking and alcohol drinking, the human genetics of drinking has been a fashionable topic for research, while the human genetics of smoking has been neglected or viewed with suspicion. The differing course of genetic themes in the alcohol and tobacco areas is discussed in relation to (a) different historical pressures which promoted disease models of alcoholism and 'bad habit' models of heavy smoking and (b) possible fundamental differences in the nature of cigarette and alcohol use. This topic is further complicated by the substantial co-occurrence of heavy smoking and heavy drinking, so that the genetic determinants may well over-lap. 'Cross-cultural' comparison of these contrasting interests in genetics is argued to be an important topic for future research.