Figure 1

Overview of ICod: network-based disease–disease similarity analysis. A. Generation of disease-related protein–protein interaction (PPI) networks based on seed genes. B. Degree of network similarity (μ) determines disease–disease similarity by analyzing the proportion of intersections between disease-related PPIs. C. Detailed example of grading PPI-based similarity between type 2 diabetes mellitus (T2DM) and obesity using ICod.