Polymorphisms in the CHRNA6 and CHRNB3 subunit genes were examined in a genetic supplemental sample participating in the National Youth Survey Family Study (NYSFS; Institute for Behavioral Science, and Institute for Behavioral Genetics, University of Colorado) wave 10. The National Youth Survey is a nationally representative probability sample of adolescents aged 11–17 in 1976 and living in the United States in 1977. A follow-up interview was conducted in 2002 (age range 35–44 years) where behavioral data and buccal cell swab samples were obtained on a strictly voluntary basis (Elliott et al, 1989). Of the 1051 individuals who agreed to follow-up interviews and provided buccal swab DNA samples, 856 of them had tried cigarettes. Although there has been some selective/disproportionate loss in some waves by sex, or age, or race/ethnicity, or social class across the first 10 waves of the NYS, these differences are quite small and often do not significantly affect the original distribution of these variables as established at the first wave of the NYS, which has been shown to be representative of individuals born in the continental U.S.
