Table 2 Number of PACs in different gene types
Constitutive IntronsRetrained Introns
Protein-Coding GenesNoncoding GenesProtein-Coding GenesNoncoding Genes
Intron number134,7082,5505,151116
No. of introns that contain PACs12,0311531205
% of introns that contain PACs8.93%6.00%2.33%4.31%
  • The percentage is calculated by (no. of introns that contains PACs)/(intron number). PACs, poly(A) site clusters.