Network Motifs

Subgraph significance · Z-scores vs random ensembles · Feed-forward loops
Network (click to rewire)
3-Node Motif Catalog
Real vs Random counts (Z-score)
16
0.20
30
Z-score: Z = (Nreal − ⟨Nrand⟩) / σrand
Feed-forward loop: A→B→C, A→C (abundant in gene networks)
Significance: |Z| > 2 → over/under-represented motif