TBLASTN commonly maps a protein to a genome or searches EST databases for related proteins not yet in the protein databases.
Net-tBlastN is a variant of the tBlastN program intended for work with distant databases.
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.