Figure 3.
Panel A. Number of subjects needed for a given effect size for a continuous trait assuming 80% statistical power, an additive model, and three alpha levels: 0.05 (1 SNP), 0.0001 (500 SNPs), and 5×10−8 (1 million SNP GWAS).
Panel B. Number of subjects needed for a given effect size (measured as an odds ratio [OR]) for a case-control design assuming 80% statistical power, a minor allele frequency (MAF) of 20%, an additive model, and three alpha levels: 0.05 (1 SNP), 0.0001 (500 SNPs), and 5×10−8 (1 million SNP GWAS).