Figure 3: How to identify agnologous molecular components across species.

(a) Definition of agnology. (b) Agnologous gene pairs can be identified through genes that connect to similar sets of genes in aligned cross-species gene networks. (c) When prior knowledge about gene sets is known, agnologous gene sets are discovered through large overlaps between gene sets across species. (d) When prior knowledge is not available, agnologous gene sets can be discovered by finding sub-networks with similar topology and expression patterns across species. (e) Resemblance at the organismal level, i.e., agnologous profiles, can be examined by comparing genomic profiles across species.