Related Experiment Video
Updated: Aug 8, 2026
10:23
Self-assembly of Complex Two-dimensional Shapes from Single-stranded DNA Tiles
Published on: May 8, 2015
Automatic generation of model sequences for complex regions in assembly graphs with TTT
Dmitry Antipov1, Ying Chen2, Marco Sollitto3
1Genome Informatics Section, Center for Genomics and Data Science Research, National Human Genome Research Institute, National Institute of Health, Bethesda, MD 20892, USA.
Cell Genomics
|August 6, 2026
Summary
We developed a new algorithm, the trivial tangle traverser (TTT), to resolve complex genome assembly tangles. TTT automates the correction of errors in chromosome assembly, improving genomic accuracy.
Area of Science:
- Genomics
- Bioinformatics
- Computational Biology
Background:
- Automated assembly of vertebrate chromosomes is advancing.
- Genome assemblers struggle with long, similar repeats, causing tangles and gaps.
- Manual curation of assembly graphs is labor-intensive and error-prone.
Purpose of the Study:
- To present the trivial tangle traverser (TTT) algorithm for resolving assembly graph tangles.
- To provide an automated and optimized solution for genome assembly challenges.
- To improve the accuracy and completeness of genome assemblies.
Main Methods:
- The TTT algorithm uses depth of coverage and read-to-graph alignment.
- A two-stage process estimates sequence multiplicities.
- Identifies traversals consistent with the underlying genomic data.
Main Results:
- TTT traversals were evaluated on the HG002 human reference genome.
- TTT was compared to a state-of-the-art assembler on the giraffe T2T assembly.
- TTT characterized a previously unassembled gene array in the zebra finch.
Conclusions:
- TTT offers an optimized resolution for assembly graph tangles.
- The algorithm improves the handling of complex genomic regions.
- TTT enhances the accuracy of telomere-to-telomere genome assemblies.
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