Network topology of porcine expression atlas. The collapsed cluster diagram shown here is a simplified view of the graph used for this analysis and shown in Figure 1. Each node represents one of the 150 largest clusters of genes, the size of the node being proportional to the number of individual nodes (probesets) within that cluster. Edges represent connections between clusters whereby nodes in one cluster share edges with nodes in another. The color of the nodes has been selected to represent clusters of genes expressed in given types of tissues which tend to group together with the overall topology of the network.