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PSIBLAST_PairwiseStatSig: reordering PSI-BLAST hits using pairwise statistical significance
1Department of Computer Science, Iowa State University, Ames, IA 50011-1041, USA. ankitag@cs.iastate.edu
Bioinformatics (Oxford, England)
|March 3, 2009
Summary
We developed a tool to improve sequence similarity searches by reordering results using pairwise statistical significance. This enhances the accuracy of tools like PSI-BLAST while maintaining their speed.
Area of Science:
- Bioinformatics
- Computational Biology
- Genomics
Background:
- BLAST and PSI-BLAST are standard tools for sequence similarity searching.
- Current methods may lack precision in ranking search results.
- Pairwise statistical significance shows promise for improving retrieval accuracy.
Purpose of the Study:
- To introduce an add-on for BLAST and PSI-BLAST.
- To reorder search hits using pairwise statistical significance.
- To enhance the accuracy of sequence similarity searches.
Main Methods:
- Developed an add-on module for existing BLAST and PSI-BLAST programs.
- Implemented pairwise statistical significance calculations.
- Utilized position-specific substitution matrices for significance estimation.
Main Results:
- The add-on reorders hits based on pairwise statistical significance.
- This approach refines PSI-BLAST results by leveraging its position-specific matrices.
- The method aims for more accurate statistical significance estimates.
Conclusions:
- The add-on offers improved hit ranking for sequence similarity searches.
- It combines enhanced accuracy with the speed of BLAST/PSI-BLAST.
- This tool can lead to more precise biological sequence analysis.
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