BlastN compares a nucleotide query sequence against a nucleotide sequence database.

The program aligns sequence (input file) on the base prepared by program FormatDB.

BLAST is a service of the National Center for Biotechnology Information (NCBI). A nucleotide or protein sequence sent to the BLAST server is compared against databases at the NCBI and a summary of matches is returned to the user.

The www BLAST server can be accessed through the home page of the NCBI at www.ncbi.nlm.nih.gov. Stand-alone BLAST binaries can be obtained from the NCBI FTP site.

Reference:
Altschul, Stephen F., Thomas L. Madden, Alejandro A. Schaffer, Jinghui Zhang, Zheng Zhang, Webb Miller, and David J. Lipman (1997), "Gapped BLAST and PSI-BLAST: a new generation of protein database search programs", Nucleic Acids Res. 25:3389-3402.