SNP-trait associations that failed to achieve significance or failed to generalize to African Americans may represent lack of power or true differences in allelic architecture and/or linkage disequilibrium patterns between the two populations. To help distinguish between these two possibilities, we calculated the power to detect the mostly European-reported associations in this African American sample. Overall, 17 SNP-trait tests of association were adequately powered (>80%). Among the adequately powered tests of association, almost all (16/17) SNP-trait tests of association failed to generalize in African Americans with respect to level of significance anddirection of effect (Table 4).
