For SNPs that do not have effects, we would not expect to see any difference between markers selected with or without data integration in the replication study. To compare the 2 approaches, we therefore first selected all SNPs with P values of less than .01 to enrich for markers with effects. Figure 2 shows that SNPs selected through data integration replicated as well as SNPs selected on the basis of having the top-ranked P values in the meta-analysis without data integration. Some of the SNPs selected through data integration even had P values with ranks as high as 25 000 in the meta-analysis. The fact that such SNPs would not have been selected on the basis of their P value but do replicate demonstrates the value of considering existing data sources.
