Genomics data standards & GA4GH
Last reviewed: 2026-07-08 — see the freshness policy.
Learning objectives
After this chapter you will be able to:
- Explain why genomics needs data-sharing standards beyond file formats, and how GA4GH's Driver Project model keeps those standards grounded in real deployments.
- Place the key GA4GH standards across their Work Streams — data use/identity, genomic knowledge, cloud execution, and large-scale genomics.
- Design federated, consent-aware genomic data sharing, and know where GA4GH's Cloud work stream connects to the workflow-orchestration decisions made elsewhere in this book.
Beyond FASTQ/BAM/VCF
Earlier chapters covered the pipeline file formats (FASTQ→BAM→VCF) and storing variants at scale. But genomics' real promise — discovery across populations — requires sharing data across institutions and borders, and that needs standards for how to identify a variant, how to ask who has it, how to stream it securely, who is allowed to, and — increasingly — how to run the same pipeline portably across institutions in the first place. The Global Alliance for Genomics and Health (GA4GH) publishes exactly these.
flowchart LR
VRS["VRS<br/>(normalized variant IDs)"] --> Share
Pheno["Phenopackets<br/>(phenotype + genotype)"] --> Share
Beacon["Beacon v2<br/>(discovery: who has this variant?)"] --> Share
htsget["htsget<br/>(secure streaming of reads/variants)"] --> Share
DUO["DUO + Passports<br/>(consent-aware access)"] --> Share
Cloud["WES / TES / TRS / DRS<br/>(portable execution + discovery)"] --> Share
Share["Federated, consent-aware genomic data sharing"]
GA4GH as an organization: Driver Projects and Work Streams
GA4GH is not just a list of specifications — it's an international standards body that deliberately grounds every standard in a real deployment before finalizing it. Driver Projects are large genomics initiatives (national sequencing programs, research consortia, disease-matching networks) that supply real requirements and pilot each standard before it's broadly adopted; well-known examples include the 1000 Genomes Project, the Genomics England 100,000 Genomes Project, the US All of Us Research Program, ClinGen, and the Matchmaker Exchange (covered below). This Driver Project discipline is why GA4GH standards tend to solve real interoperability problems rather than theoretical ones — worth knowing when you're deciding whether to adopt a GA4GH standard or build something bespoke.
The standards themselves are organized into Work Streams, each covering a different layer of the sharing problem:
| Work Stream | Covers | Standards in this chapter |
|---|---|---|
| Data Use & Researcher Identities | Consent and authorization | DUO, Passports |
| Genomic Knowledge Standards | Representing variants and phenotypes computably | VRS, Phenopackets |
| Cloud | Portable execution and tool discovery | WES, TES, TRS, DRS |
| Large Scale Genomics | Efficient, secure access to sequence data | htsget, RefGet, Crypt4GH |
| Discovery | Federated search without exposing records | Beacon |
The key GA4GH standards
| Standard | Purpose |
|---|---|
| VRS (Variation Representation Spec) | A computable, normalized way to represent and identify a variant — so the same variant gets the same ID everywhere, enabling federated matching. |
| Phenopackets | A computable package of an individual's phenotype + disease + genotype; interoperates with FHIR for precision-medicine exchange. |
| htsget | Secure HTTP streaming of reads/variants (BAM/CRAM/VCF) by genomic region — fetch a gene's worth of data without moving whole files. |
| Beacon (v2) | A discovery API: "does any dataset have this variant / this query?" — answers without exposing record-level data. |
| DUO (Data Use Ontology) | Machine-readable encoding of a dataset's permitted uses/consent (e.g. "disease-specific research only"). |
| Passports / AAI | Standardized researcher authentication and authorization for controlled-access data. |
| RefGet | Retrieves a reference sequence by a checksum-based identifier instead of a filename — removes ambiguity about which exact reference build a coordinate is relative to. |
| Crypt4GH | A file-encryption standard for genomic files at rest and in transit, used by archives like the European Genome-phenome Archive (EGA) to keep files encrypted end-to-end outside a trusted enclave. |
| WES (Workflow Execution Service) | A common REST API for submitting and monitoring a workflow run, regardless of the underlying engine. |
| TES (Task Execution Service) | A common API for executing one containerized task on diverse compute backends — the portable layer underneath a workflow engine. |
| TRS (Tool Registry Service) | A common API for describing and discovering versioned bioinformatics tools and workflows (implemented by registries like Dockstore). |
The Cloud work stream: portable execution standards
This is the part of GA4GH most directly relevant to genomics workflow orchestration: WES, TES, and TRS sit as a common API layer above the workflow engines (Nextflow, WDL/Cromwell, CWL) that chapter already covers.
flowchart TB
Client["Client / platform"] -->|"submit run via WES"| WES["WES (common API)"]
WES --> Cromwell["Cromwell (WDL)"]
WES --> Toil["Toil (CWL)"]
WES --> NFEngine["Nextflow"]
Cromwell & Toil & NFEngine -->|"execute one task via TES"| TES["TES-compatible compute backend"]
TRS["TRS — discover/describe<br/>the versioned workflow"] -.-> Client
- WES means a platform can submit a workflow run and poll its status through one API, without caring whether the workflow underneath is running on Cromwell, Toil, Arvados, or another WES-compatible engine — the same "portable interface over different engines" idea as FHIR profiles standardize different EHRs, applied to workflow execution instead of clinical data.
- TES standardizes the layer below that: how a single containerized task gets executed on a given compute backend, so a workflow engine can target multiple clouds' compute through one interface instead of a bespoke integration per cloud.
- TRS solves tool/workflow discovery — "which version of this pipeline did you run, and where do I get it" — the same provenance question Data lineage & provenance raises generally, applied specifically to versioned workflow definitions. Dockstore is the best-known TRS-compliant registry.
Design implication: if workflow orchestration already told you to standardize on a portable workflow language and containerize every step, WES/TES/TRS are the next layer of that same portability discipline — worth adopting when you need to submit workflows to infrastructure you don't fully control (a multi-institution consortium, a national genomics platform) rather than only to your own known cluster.
Reference genomes (get this right first)
Every coordinate is relative to a reference genome. Mixing references silently corrupts analysis. Know which you're on:
- GRCh37 (hg19) — legacy, still common in older pipelines and databases.
- GRCh38 (hg38) — the current mainstream reference.
- T2T-CHM13 — the first complete (telomere-to-telomere) human genome; increasingly used for hard regions.
Record the reference assembly with the data, and use VRS (which is assembly-aware) when sharing variant identity across systems. RefGet goes a step further: instead of trusting a filename or a loosely-versioned label like "hg38" (which can itself mean slightly different builds depending on the source), it identifies a reference sequence by a checksum of its content — so two systems can confirm they mean the exact same reference bytes, not just the same nominal name.
Federated, consent-aware sharing
The standards compose into a pattern where data stays home and only answers travel:
- Discovery — a Beacon lets a researcher ask whether a cohort contains a variant of interest, without downloading anything.
- Access control — DUO tags each dataset's allowed uses; Passports carry the researcher's authorizations; together they enforce consent at query time.
- Retrieval — once authorized, htsget streams just the needed regions.
- File-level protection — Crypt4GH keeps files encrypted at rest and in transit, so an archive operator storing the data doesn't need to be a fully trusted party with plaintext access.
- Identity & phenotype — VRS normalizes variant identity; Phenopackets (and FHIR) carry the linked phenotype.
This is the genomics counterpart to the privacy-preserving patterns in de-identification & consent and RWD tokenization: genomic data is inherently re-identifying, so federation + consent-aware access beats copying data around.
Case study: Matchmaker Exchange
Matchmaker Exchange is a real, running federated network for rare-disease diagnosis: a clinician with an undiagnosed patient's genotype and phenotype profile queries the network, which fans the query out across independently-operated national and institutional nodes (including systems like PhenomeCentral, GeneMatcher, and DECIPHER) to find other clinicians or researchers who have seen a similar profile — without any node exposing its full patient dataset to the others. It's a concrete, working instance of exactly the pattern this chapter describes: Beacon-style discovery, phenotype/genotype representation aligned with Phenopackets, and consent-respecting federation, deployed for a problem (diagnosing ultra-rare diseases where no single institution has enough cases) that federation makes newly solvable.
Architecture implications
- Adopt GA4GH for cross-org sharing rather than bespoke APIs — it is the lingua franca of genomic networks (national programs, research consortia), and its Driver Project model means the standards were shaped by organizations solving the same problem you likely have.
- Pin the reference assembly everywhere and use VRS/RefGet for portable, unambiguous variant and reference identity.
- Enforce DUO/consent at query time, not by trust — the variant store and access layer must check permitted use.
- Bridge to the clinic via Phenopackets ↔ FHIR so genotype and phenotype stay linked (key for oncology and rare disease).
- Adopt WES/TES/TRS when submitting workflows to infrastructure you don't own — a consortium or national platform — rather than only when running on your own cluster, where the workflow orchestration engine choice alone is usually sufficient.
Check yourself
- What problem does VRS solve that a chromosome-position-ref-alt string does not, and how does RefGet solve the analogous problem for the reference sequence itself?
- How do Beacon, DUO, and Passports combine to share data without copying it?
- Why would a platform submitting workflows to a multi-institution consortium want a WES-compatible API layer above its chosen workflow engine, rather than integrating with that engine directly?
- What real problem does the Matchmaker Exchange solve that a single institution's own patient database cannot?