Animal Genomics · VGP-Standard Assemblies

Reference-grade genomes to VGP standards.

Whether the goal is a de novo reference for a non-model species, a livestock pan-genome, or a conservation genomics programme, the modern standard is the same: a complete, accurate, chromosome-scale assembly. Nucleome Informatics builds animal genomes with the HiFi + ultra-long ONT + Hi-C stack that defines current best practice.

Plan Your Project → Learn the Basics
VGP-standard
assemblies
HiFi + UL-ONT + Hi-C
stack
Sex chromosomes & mitogenome
resolved
Livestock, wildlife & companion
species
About the Service

Animal Genome Sequencing at Nucleome Informatics

Animal genomes range from compact (some birds ~1 Gb) to very large (some amphibians and lungfish exceed 50 Gb), with repeat content, heterozygosity, and sex-chromosome architecture varying enormously. Nucleome Informatics offers:

  • Chromosome-scale assembly with full QC (QV, BUSCO, Merqury, contig N50, per-chromosome gap status)
  • Haplotype-resolved output where data supports phasing
  • Mitochondrial genome (circularised, annotated)
  • Repeat landscape and gene prediction support (with RNA-seq evidence where available)
  • Resequencing deliverables: variant calls, population structure, diversity metrics, GWAS-ready genotypes
  • NCBI submission-ready files and publication-grade methods documentation

Why this approach

  • QV ≥40, Mb-scale contigs
  • Phased, chromosome-scale
  • Sex chromosomes attempted honestly
Learning Path

From first principles to expert-level analysis

New here? Start with Foundations. Planning a study or reviewing results? Jump to Practitioner or Expert. Each level builds on the one before it, so you can read this page as a short course or dip in where you need to.

Start here if you are new to this service — six ideas that explain what it is and why it matters.

LEVEL 1

What is a reference genome?

A high-quality assembly of one individual's genome that serves as the coordinate system for all subsequent comparisons in that species — the foundation resource for a research programme.

LEVEL 1

What are VGP standards?

The Vertebrate Genome Project's quality benchmarks for reference assemblies: near-error-free sequence (QV ≥40), highly contiguous (Mb-scale contigs), complete (≥95% gene completeness), and phased.

LEVEL 1

Why long reads?

Animal genomes contain repeats, segmental duplications, and GC-extreme regions that fragment short-read assemblies. Long reads assemble them correctly — often into chromosome-scale sequences.

LEVEL 1

What species can be sequenced?

Any animal with sufficient DNA: mammals, birds, reptiles, amphibians, fish, insects, molluscs. Genome size and repeat content determine data requirements.

LEVEL 1

What is a haplotype-resolved assembly?

Separate assemblies of the two parental haplotypes — essential for heterozygous outbred individuals, where a single "consensus" assembly would merge the parents' genomes incorrectly.

LEVEL 1

What do I provide?

High-quality HMW DNA (blood or tissue; we provide protocols), plus optional parental samples for triad phasing and cohort samples for resequencing.

For scientists planning a project or reading a report: how each step works and how it can mislead.

LEVEL 2

Genome scoping

Genome size, heterozygosity, and repeat content are estimated (k-mers, close relatives) before sequencing; data volumes and strategy follow.

LEVEL 2

The assembly stack

HiFi (Revio) for accuracy; ultra-long ONT (PromethION) for span; Hi-C for scaffolding and phasing; hifiasm/Verkko assembly with haplotype-aware configuration.

LEVEL 2

Sex chromosomes

The repeat-rich Y/W chromosomes are the hardest targets; ultra-long reads and high coverage give the best chance of assembly, with per-chromosome status reported honestly.

LEVEL 2

Annotation

Repeat annotation, gene prediction (BRAKER/MAKER with RNA-seq evidence), and functional annotation; comparative genomics against related species.

LEVEL 2

Resequencing and population analysis

Cohort resequencing delivers variant calls, population structure (PCA/ADMIXTURE), diversity and inbreeding metrics, and GWAS-ready genotypes for livestock programmes.

LEVEL 2

Conservation applications

Genomic diversity, inbreeding (runs of homozygosity), effective population size, and population structure analyses support management decisions for endangered and captive populations.

For study design: the decisions that determine whether the data answers your question.

LEVEL 3

Reference individual choice

Inbred or low-heterozygosity individuals simplify assembly; for outbred wildlife, haplotype-resolved output is the honest target. Choose the reference individual deliberately — it becomes the species' coordinate system.

LEVEL 3

Livestock pan-genomes

Multi-breed reference panels capture breed-specific structural variation that single references miss; we support pan-genome construction and graph-based genotyping.

LEVEL 3

GWAS in livestock

Trait associations (growth, disease resistance, fertility) via mixed models (GEMMA/GCTA; GAPIT for breeding contexts), with imputation strategies for cost-efficient cohort genotyping (see our SNP Genotyping/GWAS page).

LEVEL 3

Conservation genomics programme design

Sampling design matters: geographic coverage, sample numbers per population, and reference quality determine what demographic questions the data can answer. We advise before sampling.

LEVEL 3

Cytogenetic integration

Chromosome-scale assemblies can be anchored to karyotypes (with cytogenetic data) — valuable for species with unusual chromosome evolution.

LEVEL 3

Submission and publication

NCBI submission-ready assemblies and raw data, with full methods documentation for the description paper.

VGP
Vertebrate Genome Project; source of the reference-assembly quality standards.
QV
quality value; base-level consensus accuracy (QV 40 ≈ 1 error per 10 kb).
Runs of homozygosity
long homozygous tracts indicating recent inbreeding.
Triad phasing
phasing an offspring assembly using parental sequencing data.
Segmental duplication
duplicated genomic segments complicating assembly.
Effective population size (Ne)
the genetic measure of a population's breeding size.
The Science

How it works, in two figures

The VGP quality standards and the complete assemblies that defined them (Rhie et al. 2021; the complete human genome, Nurk et al. 2022) establish the benchmarks we apply; livestock and conservation genomics applications are established in the animal genetics literature. See references below.

Figure 1 Assembly quality ladder. schematic
Draft assembly VGP-grade assembly Fragmented at repeats and duplications Sex chromosomes unresolved No phasing QV ≥40, Mb-scale contigs Phased, chromosome-scale Sex chromosomes attempted honestly
Figure 1 | Assembly quality ladder. (Illustrative schematic, not sample data.)
Figure 2 Workflow. schematic
Genome scoping HMW DNA HiFi + UL-ONT + Hi-C Haplotype-resolved assembly Annotation + mitogenome Population resequencing
Figure 2 | Workflow. (Illustrative schematic, not sample data.)
Technology Highlights

Built for the questions you are asking

The platforms, pipelines and standards behind this service.

PacBio HiFi on Revio

≥99.9% accurate reads — the accuracy backbone of VGP-grade assemblies.

Ultra-long Oxford Nanopore reads

PromethION reads spanning 50–100+ kb close centromeres, rDNA arrays, and the largest segmental duplications.

Hi-C scaffolding and phasing

Chromosome-scale scaffolding plus haplotype phasing from proximity-ligation data; parental data (triad phasing) where available.

VGP quality benchmarks

Assemblies judged against Vertebrate Genome Project standards: QV ≥40, contig N50 in the Mb range, gene completeness ≥95%, and phased chromosomes.

Sex chromosome resolution

Long reads resolve the repeat-rich Y and W chromosomes that short-read assemblies reduce to placeholders — where coverage and span permit, reported honestly where they do not.

Population and conservation genomics

Resequencing pipelines for diversity metrics, inbreeding estimation (runs of homozygosity), demographic inference, and GWAS for livestock traits. ---

Scope Note

What this service does and does not cover

Scope note. Assembly outcomes scale with genome size, repeat content, and heterozygosity: compact, low-heterozygosity genomes routinely reach VGP-grade; very large or highly heterozygous genomes reach chromosome-scale reference grade with per-chromosome status reported honestly. Sex chromosome completeness depends on read span and coverage. Gene prediction without RNA-seq evidence is model-based; transcriptome support is recommended for publication-grade annotation.---
Why Nucleome

Service highlights

What you can expect from our team in Hyderabad.

VGP-standard targets

Quality benchmarks agreed and reported — not asserted.

The full stack in-house

HiFi, ultra-long ONT, Hi-C, and Illumina from one Hyderabad laboratory.

Sex chromosomes attempted, honestly reported

The hardest chromosomes get the best data — and honest status reporting.

Livestock and conservation pipelines

From reference assembly to GWAS, diversity, and inbreeding analyses.

Indian fauna and livestock relevance

Experience with Indian livestock breeds, wildlife, and aquaculture species.

NCBI-ready deliverables

Submission-formatted assemblies, annotation, and methods for publication. ---

Questions

Frequently asked, in plain language

From the basics to the finer points of design and interpretation.

basicWhat quality standard do you target?
VGP-grade benchmarks where the genome permits: QV ≥40, Mb-scale contig N50, ≥95% gene completeness, phased chromosomes. Targets are agreed at project design and reported honestly.
basicWhat do you need from me?
High-quality HMW DNA (blood or tissue), ideally from a low-heterozygosity reference individual, plus optional parental samples for phasing.
basicIs the mitochondrial genome included?
Yes — a circularised, annotated mitogenome is included with every nuclear project.
intermediateCan you assemble the Y chromosome?
We attempt it with ultra-long reads and high coverage; Y/W chromosomes are the hardest targets and per-chromosome status is reported honestly.
intermediateCan you resequence my cohort afterwards?
Yes — short-read resequencing with variant calling, population structure, diversity/inbreeding metrics, and GWAS-ready genotypes.
intermediateHow does this support conservation programmes?
A reference genome plus population resequencing delivers diversity, inbreeding, and structure analyses that inform management decisions.
advancedCan you build a livestock pan-genome?
Yes — multi-breed reference panels with pan-genome and structural-variant analysis, plus graph-based genotyping options.
advancedCan GWAS be run on my livestock cohort?
Yes — mixed-model association (GEMMA/GCTA; GAPIT for breeding contexts) with imputation strategies for cost-efficient genotyping; see our SNP Genotyping/GWAS page.
advancedHow do you handle very large genomes (amphibians, lungfish)?
Genome size drives data volume and cost; the strategy (HiFi + UL-ONT + Hi-C) is the same, scaled. We scope feasibility and data volumes honestly at design stage.
advancedCan assemblies be anchored to karyotypes?
Yes, where cytogenetic data is available — valuable for species with unusual chromosome evolution.
References

Key literature & resources

Selected sources behind the methods and reference values on this page. Figures labelled "schematic" or "illustrative" are generated for this page, not client data.

  1. Rhie A, et al. Towards complete and error-free genome assemblies of vertebrate genomes (VGP quality standards). Science. 2021;374(6566):367–373.
  2. Nurk S, et al. The complete sequence of a human genome. Science. 2022;376(6588):eabj6987.
  3. Cheng H, et al. Haplotype-resolved de novo assembly with phased assembly graphs (hifiasm). Nature Methods. 2021;18(2):170–175.
  4. Rautiainen M, et al. Telomere-to-telomere assembly of diploid chromosomes with Verkko. Nature Methods. 2023;20(10):1544–1552.
  5. Dudchenko O, et al. De novo assembly of the Aedes aegypti genome using Hi-C. Science. 2017;356(6333):92–95.
  6. Simão FA, et al. BUSCO. Bioinformatics. 2015;31(10):1670–1676. (Merqury: Rhie A, et al. Genome Biology. 2020;21(1):245.)
  7. Yang J, et al. GCTA. American Journal of Human Genetics. 2011;88(1):76–82. (GAPIT: Lipka AE, et al. Bioinformatics. 2012;28(18):2397–2399.)
  8. Kardos M, et al. — genomic consequences of inbreeding (runs of homozygosity framework): see also Ceballos FC, et al. Runs of homozygosity: windows into population history and trait architecture. Nature Reviews Genetics. 2018;19(4):220–234.