# Sequence Types and Features Ontology (SO)

> SO is a collaborative ontology project for the definition of sequence features used in...

- Page: https://library.schematica.io/model/10eb7680113f4f0583f9be91a9005cc9
- Model type: Ontology
- License: CC BY 4.0
- Access type: Free
- Access method: Download
- Model size: Mid
- Formats: OWL
- Domains: Healthcare
- External link: https://bioportal.bioontology.org/ontologies/SO
- Contact: SO Administrators (song-devel@lists.sourceforge.net)
- Listed in library: 2025-06-12
- Last updated: 2025-09-10

## Description

## Ontology Info

| Field | Value |
|-------|-------|
| Acronyme | SO |
| Description | SO is a collaborative ontology project for the definition of sequence features used in biological sequence annotation. SO was initially developed by the Gene Ontology Consortium. Contributors to SO include the GMOD community, model organism database groups such as WormBase, FlyBase, Mouse Genome Informatics group, and institutes such as the Sanger Institute and the EBI. Input to SO is welcomed from the sequence annotation community. The OBO revision is available here: http://sourceforge.net/p/song/svn/HEAD/tree/ |
| Format | OWL |
| Categories | Genomic and Proteomic |
| Groups | OBO Foundry |

## Metrics

| Metric | Value |
|--------|-------|
| Classes | 2,736 |
| Individuals | 0 |
| Properties | 50 |
| Max Depth | 13 |
| Max Child Count | 45 |
| Average Child Count | 3 |
| Classes With One Child | 132 |
| Classes With More Than 25 Children | 7 |
| Classes With No Definition | 204 |

## Projects using SO

- [Beta Cell Genomics database](https://bioportal.bioontology.org/projects/BCGD)
- [Computational Biology Institute of Montpellier](https://bioportal.bioontology.org/projects/IBC)
- [FlyBase](https://bioportal.bioontology.org/projects/FlyBase)
- [Gramene](https://bioportal.bioontology.org/projects/Gramene)
- [SGD](https://bioportal.bioontology.org/projects/SGD)
- [Bioinformatics Web Service Ontology](https://bioportal.bioontology.org/projects/BWSO)
- [NGS Ontology](https://bioportal.bioontology.org/projects/NGSOnto)
- [MBGD SPARQL Search](https://bioportal.bioontology.org/projects/MBGD)
- [WormBase](https://bioportal.bioontology.org/projects/WormBase)
- [Fishmap](https://bioportal.bioontology.org/projects/Fishmap)
- [TAIR](https://bioportal.bioontology.org/projects/TAIR)
- [wFleaBase](https://bioportal.bioontology.org/projects/wFleaBase)
- [ParameciumDB](https://bioportal.bioontology.org/projects/ParameciumDB)
- [dictyBase](https://bioportal.bioontology.org/projects/dictyBase)
- [Fantom5 Nanopublications](https://bioportal.bioontology.org/projects/Fantom5+Nanopubs)
- [Schizosaccharomyces pombe](https://bioportal.bioontology.org/projects/SP)
- [Mouse Genome Informatics](https://bioportal.bioontology.org/projects/MGI)

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Source: https://library.schematica.io/model/10eb7680113f4f0583f9be91a9005cc9