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Updated: Jun 14, 2026

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Novel Sequence Discovery by Subtractive Genomics
Published on: January 25, 2019
Storage and retrieval of highly repetitive sequence collections
Veli Mäkinen1, Gonzalo Navarro, Jouni Sirén
1Department of Computer Science, University of Helsinki, Helsinki, Finland . vmakinen@cs.helsinki.fi
Summary
New full-text indexes efficiently analyze repetitive sequence collections, like genomes, by reducing space requirements. This enables faster in-memory analysis of large datasets with improved compression models.
Area of Science:
- Bioinformatics
- Computational Biology
- Data Compression
Background:
- Repetitive sequence collections, such as individual genomes, present analysis challenges due to their large size.
- Suffix trees are powerful tools for sequence analysis but require significant memory.
- Existing compressed suffix trees struggle with long-range repetitiveness.
Purpose of the Study:
- To develop novel static and dynamic full-text indexes for efficient analysis of highly repetitive sequence collections.
- To reduce the space complexity of suffix tree-based analyses.
- To enhance the capability of compressed suffix trees to capture longer-term repetitiveness.
Main Methods:
- Development of new static and dynamic full-text indexes.
- Integration of these indexes with a dynamic fully-compressed suffix tree.
- Focus on space complexity proportional to typical sequence length plus edit operations.
Main Results:
- The new indexes effectively capture high repetitiveness in sequence collections.
- Achieved space complexity is proportional to one typical sequence length plus total edit operations.
- Experimental results demonstrate the practicality and efficiency of the proposed methods.
Conclusions:
- The developed full-text indexes offer a practical solution for analyzing large, repetitive sequence collections.
- These indexes significantly reduce memory requirements for suffix tree-based analyses.
- The approach enhances the ability to handle complex, long-range repetitiveness in genomic and other sequence data.
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