This led to much larger GWAS analyses in collaborative samples, which has proven remarkably successful for many diseases. As discussed in the next section, most of the new, highly significant findings have been for alleles with GRRs of 1.1-1.4, mostly between 1.12-1.20. In this range (Figure 1), good or excellent power requires samples of 8,000-20,000 cases (plus controls), depending on GRR and allele frequency – i.e., larger than any sample collected by a single research group to date.
