Sections
Personal tools

Summary

Sequence Comparison: Summary

  • Dynamic programming finds the optimal alignment between two sequences in a computing time proportional to NxM, where N and M are the sequence lengths
  • Critical user choices include the scoring matrix, the gap penalties, and the algorithm (local, or global)
  • FASTA and BLAST applies heuristics to speed up database search
  • Statistics on local sequence alignments are defined by: raw score, bit score, E-values and P-values
  • BLAST reports a "database" E-value, that takes into account the total number of residus in the sequence database