Definition and characterization of preserved intramodular hub genes. The scatterplots show how the combined measure of module membership in blood MM.combined.Blood (or MM.Blood, y-axis) related to the analogous measure in cortex (a), caudate nucleus (b), and cerebellum (c). Preserved intramodular hub genes were defined as those genes whose combined MM measure in blood and brain tissue is larger than +0.35 (or smaller than -0.35), since these genes showed highly significant evidence of being part of the preserved modules in both tissues. For the CTX, CN, and CB networks, the roughly 300 preserved intramodular hub genes are colored in red (a), yellow (b), and blue (c). We report both uncorrected correlation test p-values and Bonferroni corrected p-value (inside of brackets). Barplots (d-f) show the mean heritability of the blood expression profiles (y-axis) across preserved intramodular hub genes (blue bars), across genes in the CTX (d), CN (e), and CB (f) networks (black bars), and across all genes on the blood array (grey bar). Note that the preserved intramodular hub genes have significantly higher mean heritability than non-preserved intramodular hub genes. Barplots (g-i) show the mean blood expression values (y-axis) across the same groups of genes. Note that the preserved intramodular hub genes and the brain network genes have significantly higher mean expression values in blood than all genes on the array (grey bar). However, preserved intramodular hub genes do not have higher mean expression levels than the (roughly 2500) genes that form the brain network (black bars).