Introduction to BLAST

BLAST is NCBI’s Basic Local Alignment Search Tool. A gene(s) or protein(s) can be aligned to a genome, collection of genes or collection of proteins. There are four BLAST programs.

There are four programs in blast that you can choose from.

Query Type Database Type BLAST Program
Nucleotide Nucleotide blastn: Search a nucleotide database using a nucleotide query.
Nucleotide Protein blastx: Search protein database using a translated nucleotide query.
Protein Nucleotide tblastn: Search translated nucleotide database using a protein query.
Protein Protein blastp: Search protein database using a protein query.

Index

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