determining both the individual and the cumulative effects of rare and common variants in 30 candidate genes implicated in ND. Rare variants in NRXN1, CHRNA9, CHRNA2, NTRK2, GABBR2, GRIN3A, DNM1, NRXN2, NRXN3, and ARRB2 were found to be significantly associated with smoking status in 3,088 AA samples, and a significant excess of rare variants exclusive to EA smokers was observed in NRXN1, CHRNA9, TAS2R38, GRIN3A, DBH, ANKK1/DRD2, NRXN3, and CDH13. The 18 genetic loci implicated in targeted sequencing studies are marked in Figure 1.
