Normalized frequency distribution of tissue specific eccentricity. The distribution (i.e., normalized frequency) of the gene eccentricity centralities for each of the tissue specific interactome networks (the same 79 human tissues profiled in Figure 4). Different network groups can be classified on the basis of the maximal value of the eccentricity distribution. Some network groups have a differential maximal value of distribution, and immune cells had the lowest values. The lower eccentricity values of immune cells reinforce the postulate that immune genes have robust reach throughout the human interactome. Equal colors in the legend correspond to equal maximal values of the normalized eccentricity.