An in-depth understanding of the role of APBB1 in tobacco smoking will not only provide insights into the etiology of ND, but also reveal its protective effect on cognitive function. In this study, we performed a family-based genetic association study of APBB1 with ND in a sample consisting of 2,037 participants of African-American (AA) and European-American (EA) origin. Both individual SNP-and haplotype-based association analyses indicated that APBB1 is significantly associated with ND in both ethnic populations.
