BLAST searches and related applications are essential for analyzing gene and protein sequences. Define BLAST, describe basic features of this bioinformatics tool, and provide an example of information provided by a BLAST search.

BLAST stands for Basic Local Alignment Search Tool. It is a widely used online software platform in the field of bioinformatics, which helps scientists analyze and find similarities between gene and protein sequences. Think of it like a search engine that helps to find matching patterns between these sequences.

BLAST has several key features which make it a valuable tool in bioinformatics: 1. Fast and accurate: BLAST can quickly search through large databases to find similarities. 2. Comparing sequences: It compares the input sequence (query) against a database of known sequences, which could be either DNA or protein. 3. Scoring system: BLAST assigns scores based on matches, mismatches, and gaps in the alignment. This helps scientists assess the quality of the match. 4. Different BLAST algorithms: There exist various BLAST algorithms, such as BLASTN, BLASTP, and BLASTX, to cater for different types of sequence comparisons.

Let's say a researcher has identified a new DNA sequence from a particular organism. They want to know if this DNA sequence is similar to any known genes in other organisms. 1. The researcher would input their DNA sequence into the BLAST search tool. 2. They would choose which type of BLAST algorithm to use (in this case, BLASTN, which compares DNA sequences) and which database to search against. 3. BLAST then compares the input sequence to all the sequences in the selected database and provides a list of matches ranked by the alignment score. 4. The researcher can analyze the results to determine if their new DNA sequence shares significant similarity with any known genes, which could provide insights into its function or evolutionary history.