Figures 1–7 consist of Q-Q plots for each of the EEG measures of observed p-values against expected p-values under the null distribution, using the additive inverse of log10(p) to emphasize small p-values. There is no evidence in these plots of inflation that might be due to population stratification in allele frequencies unrelated to outcome measure. Genomic inflation factors associated with each analysis are close to 1, ranging from .97 to .99, confirming that the observed values conform to our expectation. In addition, however, none of the p-values approaches the significance threshold of 5 × 10−8. Figures 8–14 give the corresponding Manhattan plots, which order values of −log10(p) by the location of the SNP associated with it on each chromosome. These are unremarkable and do not reveal any obvious local signal. Results for all SNPs associated with p-values less than 10−4 are documented in Tables S1–S7.
