highly significantP < 0.0001
This analysis included > 300 families homologous to multi-pathway proteins and > 600 families homologous to other proteins, and revealed that the average frequencies of both insertions and deletions of the multi-pathway families were ~30% higher than those of others (insertions: 3.01 versus 2.42; deletions: 8.79 versus 6.29) (Additional file 4 ) and the differences were highly significant (P < 0.0001; T-test).