Standard Article

BLAST Algorithm

  1. Stephen F Altschul

Published Online: 23 SEP 2005

DOI: 10.1038/npg.els.0005253



How to Cite

Altschul, S. F. 2005. BLAST Algorithm. eLS. .

Author Information

  1. National Center for Biotechnology Information, Bethesda, Maryland, USA

Publication History

  1. Published Online: 23 SEP 2005

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BLAST is an acronym for basic local alignment search tool; the BLAST family of database search programs takes as input a query DNA or protein sequence, and search DNA or protein sequence databases for similarities that may indicate homology. The programs implement variations of the BLAST algorithm, which is a heuristic method for rapidly finding local alignments with scores sufficiently high to be statistically significant.


  • local alignment;
  • homology search;
  • sequence similarity;
  • statistical significance;