BLAST Link. BLink displays the results of BLAST searches that have been done for every protein sequence in the Entrez Protein data domain. It can be accessed by following the BLink link displayed beside any hit in the results of an Entrez Protein search. In contrast to Entrez's Related Sequences feature, which lists the titles of similar sequences, BLink displays the graphical output of precomputed blastp results against the non-redundant (nr) protein database. The output includes the positions of up to 200 BLAST hits on the query sequence, scores, and alignments. BLink offers a variety of display options, including the distribution of hits by taxonomic grouping, the best hit to each organism, the protein domains in the query sequence, similar sequences that have known 3D structures, and more. Additional options allow you to specify from which taxa you would like to exclude, increase, or decrease the BLAST cutoff score or filter the BLAST hits to show only those from a specific source database, such as RefSeq or SWISS-PROT. See the BLink help document for additional information.