LoMA

LoMA reconstructs localized assemblies from long-read sequencing data to resolve repetitive regions in human genomes at single-base resolution.


Key Features:

  • Highly Accurate Consensus Sequences: Constructs consensus sequences from long reads using minimap2 for alignment, MAFFT for multiple sequence alignment, and a proprietary algorithm for classifying diploid haplotypes based on structural variants and consensus sequences.
  • Error Reduction: Reduces sequencing error rates from over 8% in raw long-read data to below 0.3% in consensus sequences.
  • Targeted Region Analysis: Defines target regions based on mapping patterns to focus assembly and analysis on specific genomic loci.
  • Comprehensive Insertion Cataloging: Identified thousands of insertions in human samples NA18943 and NA19240, with approximately 80% derived from tandem repeats and transposable elements, and detected processed pseudogenes, insertions within transposable elements, and insertions >10 kbp.
  • Insights into Genomic Mechanisms: Provides evidence linking short tandem duplications, gene expression, and transposons to mechanisms underlying genomic insertions.

Scientific Applications:

  • Structural Variant Discovery: Resolve true structural variations in human genomes using high-accuracy localized assemblies.
  • Repetitive Region Characterization: Characterize complex repetitive sequences, including tandem repeats and transposable elements, at single-base resolution.
  • Insertion Analysis: Catalog and characterize insertion events genome-wide, including processed pseudogenes and long insertions (>10 kbp).
  • Mechanistic Studies: Investigate associations between insertion mechanisms, short tandem duplications, transposons, and gene expression.

Methodology:

Uses minimap2 for read mapping, MAFFT for multiple sequence alignment, consensus sequence construction, a proprietary algorithm for diploid haplotype classification based on structural variants and consensus sequences, and defines target regions from mapping patterns.

Topics

Details

License:
Not licensed
Cost:
Free of charge
Tool Type:
command-line tool
Operating Systems:
Mac, Linux, Windows
Programming Languages:
Python, Shell
Added:
4/27/2023
Last Updated:
4/27/2023

Operations

Data Inputs & Outputs

Publications

Ikemoto K, Fujimoto H, Fujimoto A. Localized assembly for long reads enables genome-wide analysis of repetitive regions at single-base resolution in human genomes. Human Genomics. 2023;17(1). doi:10.1186/s40246-023-00467-7. PMID:36895025. PMCID:PMC9996862.

PMID: 36895025
PMCID: PMC9996862
Funding: - AMED: JP21km0908001 - MEXT KAKENHI: 18H05511