VRS — GA4GH Variation Representation Specification
Overview
VRS is a computational standard for the precise, unambiguous representation of genomic variation, developed by the GA4GH Genomic Knowledge Standards Work Stream and first released in 2019. Existing variant nomenclatures such as HGVS (the notation used in clinical reports and databases) allow the same variant to be described in multiple valid ways depending on genome build, transcript, and notation convention. VRS resolves this by assigning each variant a globally unique identifier computed from its intrinsic content, enabling reliable deduplication across repositories and genome builds. VRS v2.0 was approved as a GA4GH product in 2024, adding structural variation support and extensibility mechanisms.
Variation Types
VRS defines a set of variation classes including alleles (precise sequence substitutions), haplotypes (co-occurring alleles), and copy number variants. Each object’s identity is entirely determined by its content, so the same variant described independently in two different systems produces the same identifier.
Connections
- Governed by: GA4GH (GKS Work Stream)
Resources
- https://vrs.ga4gh.org (specification)
- https://github.com/ga4gh/vrs
- https://www.ga4gh.org/product/variation-representation/ (GA4GH product page)
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8929418/ (Wagner et al. 2021, Cell Genomics)
- https://www.ga4gh.org/news_item/variation-representation-specification-vrs-v2-0-is-an-approved-ga4gh-product/ (VRS v2.0 approval)