SAMBA

SAMBA enhances genome assembly contiguity by scaffolding existing assemblies and filling spanned gaps using long-read sequencing data (including third-generation ultra-long reads that can exceed one million bases) to resolve complex genomic repeats.

Key Features:

• Scaffolding and gap-filling: Integrates long-read sequencing data to scaffold contigs and compute sequences for all spanned gaps within scaffolds.
• Gap sequence computation: Fills spanned gaps by computing and inserting gap sequences rather than only re-scaffolding.
• Retention of existing assemblies: Improves contiguity without requiring a complete re-assembly of high-quality genomes.
• Repeat resolution: Leverages ultra-long read lengths to resolve complex genomic repeats that are intractable to short reads.
• Long-read coverage integration: Adds long-read coverage to previously assembled contigs to enhance structural integrity of assemblies.
• Third-generation error handling: Designed to address limitations associated with high error rates in third-generation sequencing data.
• Empirical performance: Demonstrated improved contiguity and reduced errors relative to comparable methods in comparative analyses.

Scientific Applications:

• Assembly finishing and improvement: Increase contiguity and close gaps in draft or reference genome assemblies using long reads.
• Repeat and structural resolution: Resolve complex repeats and improve representation of repetitive genomic regions using ultra-long reads.
• Assembly upgrading: Incorporate additional long-read data to upgrade existing high-quality assemblies without full re-assembly.
• Genomic research requiring high-quality assemblies: Produce longer contigs and more complete scaffolds for downstream analyses that depend on contiguous reference sequences.

Methodology:

Integrates long-read sequencing data to scaffold existing contigs, compute and fill sequences for spanned gaps, and add long-read coverage to resolve repeats while accounting for high error rates of third-generation reads.