Building the diseasome. Panel A: four different diseases (D1, D2, D3 and D4) can share relevant genes (GA, GB, GC) (left graph). Using this information, a diseasome can be built where D1 shares GA with D2, and D3 shares GC with D4 (right). Panel B: The genetic information identified above can be complemented with the interactome to build the diseasome, where the protein encoded by GB (PB) interacts with that encoded by GC (PC) (left graph). For further explanations, see text.