Co-expression module clustering of variable genes. The topographical overlap similarity  of gene pairs is shown as a heatmap for adipose (A), heart (B), kidney (C), and liver (D). Gene pairs with low similarity are shown in yellow, and those with high similarity are shown in red. Coexpression modules define highly connected sets of correlated expression profiles as indicated by colour codes in the margins of the maps. The colour names are given in Table 2. Genes are ordered within module from left to right by increasing topographical overlap with the module eigengene. Genes that are not assigned to modules are not included in this plot.