Note that none of the SNPs are significant when analyzed in the AA sample alone. However, this result underscores the advantage of using the population-by-genotype term in the full sample. A non-significant result for a SNP in the AA sample does not allow us to rule it out; it is only when we test for significant cross-population heterogeneity in the full sample that we come to the useful conclusion that three of the ten SNPs in fact can be filtered from further priority consideration.
