What is Telomere-to-Telomere (T2T) Genome Sequencing?

Telomere-to-Telomere (T2T) Genome Sequencing is an advanced genome assembly approach that reconstructs complete chromosomes from one telomere to the other with little to no gaps. Unlike conventional genome assemblies, T2T resolves highly repetitive and previously inaccessible regions, including centromeres, telomeres, and segmental duplications, delivering a more accurate and comprehensive representation of the genome.

The introduction of the T2T-CHM13 human reference genome demonstrated that fully gapless genome assemblies are now achievable, setting a new benchmark for genomic research. This breakthrough has opened new opportunities for studying genome evolution, structural variation, and complex genetic traits across diverse organisms.

Why Choose T2T Genome Sequencing?

Traditional reference genomes often contain unresolved regions because repetitive DNA is difficult to assemble using standard sequencing technologies. These missing regions can include biologically important elements that influence genome structure, function, and evolution.

T2T Genome Sequencing overcomes these challenges by providing:

• • Complete Chromosome Assemblies with minimal or no assembly gaps.

• • Resolution of Complex Genomic Regions such as telomeres, centromeres, tandem repeats, and segmental duplications.
• • Accurate Structural Variant Detection for improved genomic analysis.
• • High-Quality Reference Genomes suitable for comparative genomics, pan-genome studies, and functional research.

Our Technology Workflow

At N2Jenomics Lab Pvt. Ltd., we combine complementary long-read sequencing technologies to generate highly accurate, chromosome-level genome assemblies.

• PacBio HiFi Sequencing

High-fidelity long reads provide exceptional base-level accuracy, enabling precise assembly of complex genomic regions while maintaining excellent consensus quality.

• Oxford Nanopore Ultra-Long Sequencing

Ultra-long reads span extensive repetitive regions that are difficult to resolve with other technologies, helping generate continuous, gap-free chromosome assemblies.

• Hi-C and Bionano Optical Mapping

Long-range genomic information is integrated to correctly order, orient, and validate assembled contigs, producing reliable chromosome-scale genome assemblies with improved structural accuracy.

T2T Genome Sequencing Service Portfolio

At N2Jenomics Lab Pvt. Ltd., we provide flexible Telomere-to-Telomere (T2T) Genome Sequencing solutions designed for diverse genome sizes, complexities, and research goals. Our services combine advanced long-read sequencing technologies with robust bioinformatics to generate highly accurate, chromosome-level genome assemblies.

Our T2T Sequencing Services

• Standard T2T Genome Sequencing

Generate highly continuous, chromosome-scale genome assemblies with minimal or no gaps using long-read sequencing and advanced assembly workflows.

• Haplotype-Resolved T2T Sequencing

Reconstruct maternal and paternal chromosome sets independently to provide phased genome assemblies, enabling accurate analysis of genetic variation and allele-specific features.

Organism-Specific Solutions

• Vertebrate Genome Sequencing

Comprehensive solutions for large and complex vertebrate genomes.

• Plant Genome Sequencing

Designed for polyploid, heterozygous, and repeat-rich plant genomes. Our integrated long-read approach enables accurate assembly of complex crop, medicinal plant, and model plant genomes.

• Bacterial Genome Sequencing

Generate complete circular bacterial genomes with fully assembled plasmids, high consensus accuracy, and optional methylation analysis.

T2T Sequencing Workflow

Our standardized workflow ensures reliable, reproducible, and high-quality genome assemblies.

• • High Molecular Weight (HMW) DNA extraction
• • Long-read library preparation
• • PacBio and Oxford Nanopore sequencing
• • Hybrid genome assembly
• • Assembly polishing and quality assessment
• • Genome annotation and functional analysis
• • Final data processing and reporting

Bioinformatics Analysis

Our comprehensive bioinformatics pipeline includes:

• • Chromosome-level genome assembly
• • Assembly graph evaluation
• • Contig and Scaffold N50 statistics
• • BUSCO genome completeness assessment
• • QV and k-mer-based accuracy evaluation
• • Structural validation using Hi-C data
• • Gene prediction and genome annotation
• • Customized downstream analysis based on project requirements

Applications

T2T Genome Sequencing supports a wide range of genomic research applications, including:

• • Discovery of novel genes and structural variants
• • Analysis of telomeres, centromeres, and repetitive DNA
• • Comparative and evolutionary genomics
• • Pan-genome construction
• • Plant breeding and agricultural genomics
• • Functional and molecular genomics
• • Microbial genome characterization
• • Disease and biodiversity research

Sample Requirements

Note: Fresh samples are recommended to obtain high-quality, high-molecular-weight DNA for optimal T2T genome assembly.

Deliverables

Every project includes:

• • Raw sequencing data (FASTQ)
• • Alignment and variant files (BAM/VCF, where applicable)
• • Genome assembly files
• • Genome annotation results
• • Quality control and statistical reports
• • Graphical data summaries
• • Comprehensive project report
• • Bioinformatics documentation and data interpretation support

Why Choose N2Jenomics Lab Pvt. Ltd.?

• • Advanced PacBio HiFi, Oxford Nanopore, and Hi-C sequencing technologies
• • High-quality chromosome-level genome assemblies
• • Customized workflows for diverse organisms
• • Experienced genomics and bioinformatics specialists
• • Comprehensive sequencing, analysis, and reporting under one roof
• • Reliable, scalable, and research-focused genomic solutions

1. How does a T2T genome assembly differ from a conventional reference genome?

Traditional reference genomes often contain unresolved gaps, especially in repetitive regions such as telomeres and centromeres. In contrast, T2T genome assembly aims to generate complete, chromosome-level sequences with minimal or no gaps, providing a more comprehensive view of the genome.

2. Why are both PacBio HiFi and Oxford Nanopore ultra-long reads used?

These technologies complement each other. PacBio HiFi delivers highly accurate long reads, while Oxford Nanopore ultra-long reads span large repetitive regions that are difficult to assemble. Together, they enable highly continuous and accurate genome assemblies.

3. Is T2T Genome Sequencing suitable for polyploid plant genomes?

Yes. T2T sequencing is well suited for complex plant genomes, including polyploid species. Advanced long-read sequencing and assembly methods help accurately distinguish multiple chromosome sets, resulting in high-quality phased genome assemblies.

4. Is Hi-C sequencing required for every T2T project?

Hi-C is strongly recommended for large and complex genomes, such as those of plants and vertebrates, because it improves chromosome-scale scaffolding and assembly accuracy. For smaller genomes, including most bacteria, high-quality T2T assemblies can often be achieved without Hi-C data.