All individuals were recruited by the Collaborative Genetic Study of Nicotine Dependence (COGEND), a United States multi-site project. Cases and controls reported smoking at least 100 cigarettes lifetime, the threshold classically used to define a smoker (Centers for Disease Control and Prevention, 2006). Cases are nicotine dependent according to the Fagerström Test for Nicotine Dependence (FTND) (Heatherton et al., 1991, Heatherton et al., 1989), with an FTND score of 4 or more. Controls were never nicotine dependent and had an FTND of 0 or 1 even when smoking the most. Genome-wide and candidate gene genetic data on 1608 European-American COGEND subjects (797 cases (FTND ≥ 4), 811 controls (FTND=0) were previously reported together with an Australian sample (N= 319) (Bierut et al., 2007, Saccone et al., 2009a, Saccone et al., 2007). With additional recruitment, we have extended our U.S.-based sample and now report on 710 African-Americans (AAs) (461 cases, 249 controls) and 454 European Americans (EAs) (140 cases, 126 controls) for a total of 1164 new subjects. These subjects have been combined with the 1608 original EA subjects recruited from
