Simple Standard for Sharing Ontological Mappings (SSSOM)
SSSOM is the Simple Standard for Sharing Ontological Mappings. It comprises three distinct components that are intended to be used together to facilitate the exchange of semantic mappings:
- a machine-readable and extensible vocabulary to describe metadata of mappings;
- a data model to represent mappings and their associated metadata;
- several file formats to represent sets of mappings on disk and on the network.
Beyond defining the standard itself, the SSSOM Core Team also aims to implement open and community-driven collaborative workflows designed to evolve the standard continuously to address changing requirements and mapping practices, and to provide reference tools and software libraries for working with the standard.
SSSOM at a glance
Basic concepts
The data model of SSSOM is centered around two fundamental concepts: mappings and mapping sets.
A SSSOM mapping is a statement that there is a correspondence of some sort between two semantic entities. It comprises two components:
- The core mapping (or raw mapping), which is a triple
<subject, predicate, object>
that represents the correspondence itself between a subject entity, for example a class in an ontology, and an object entity, for example an identifier in some database, via a semantic mapping predicate, for exampleskos:exactMatch
. - Metadata that provide supplementary pieces of information about the core mapping. This notably includes information pertaining to the provenance of the statement (for example, who emitted the statement, in other words who decided that the subject and the object should be mapped) and its justification (why should the subject and the object be mapped).
A SSSOM mapping set is a collection of SSSOM mappings, with its own metadata.
The SSSOM/TSV format
The main format proposed by the SSSOM standard to exchange mapping sets is the SSSOM/TSV format. Here is a basic example of a file in that format:
#curie_map:
# FOODON: http://purl.obolibrary.org/obo/FOODON_
# KF_FOOD: https://kewl-foodie.inc/food/
# orcid: https://orcid.org/
#mapping_set_id: https://w3id.org/sssom/tutorial/example1.sssom.tsv
#mapping_set_description: Manually curated alignment of KEWL FOODIE INC internal food and nutrition database with Food Ontology (FOODON). Intended to be used for ontological analysis and grouping of KEWL FOODIE INC related data.
#license: https://creativecommons.org/licenses/by/4.0/
#mapping_date: 2022-05-02
subject_id subject_label predicate_id object_id object_label mapping_justification author_id confidence comment
KF_FOOD:F001 apple skos:exactMatch FOODON:00002473 apple (whole) semapv:ManualMappingCuration orcid:0000-0002-7356-1779 0.95 "We could map to FOODON:03310788 instead to cover sliced apples, but only ""whole"" apple types exist."
KF_FOOD:F002 gala skos:exactMatch FOODON:00003348 Gala apple (whole) semapv:ManualMappingCuration orcid:0000-0002-7356-1779 1
KF_FOOD:F003 pink skos:exactMatch FOODON:00004186 Pink apple (whole) semapv:ManualMappingCuration orcid:0000-0002-7356-1779 0.9 "We could map to FOODON:00004187 instead which more specifically refers to ""raw"" Pink apples. Decided against to be consistent with other mapping choices."
KF_FOOD:F004 braeburn skos:broadMatch FOODON:00002473 apple (whole) semapv:ManualMappingCuration orcid:0000-0002-7356-1779 1
Quick links
General
Publications
- A Simple Standard for Sharing Ontological Mappings (SSSOM) (initial publication in Database)
- A Simple Standard for Ontological Mappings 2022: Updates of data model and outlook (paper and presentation at the Ontology Matching Workshop 2022)
- A Simple Standard for Ontological Mappings 2023: Updates on data model, collaborations and tooling (paper and presentation at the Ontology Matching Workshop 2023)
- Other presentations
Related software
- SSSOM Toolkit (reference implementation of the standard, in Python)
The SSSOM Core Team
Contact
The preferred way to contact the SSSOM team is through the issue tracker (for problems with SSSOM) or the GitHub discussion forums (for general questions).
You can find any of the members of the SSSOM core team on GitHub. Their GitHub profiles usually also provide email addresses.
You can also reach us in the OBO Foundry Slack, in the #sssom
channel.
Documentation/specification editors
- Nicolas Matentzoglu (Semanticly Ltd; @matentzn)
- Chris Mungall (LBL)
- Ernesto Jimenez-Ruiz (City, University of London)
- John Graybeal (Stanford)
- William Duncan (LBL)
- David Osumi-Sutherland (EMBL-EBI)
- Simon Jupp (SciBite)
- James McLaughlin (EMBL-EBI)
- Henriette Harmse (EMBL-EBI)
- Tiffany Callahan (@callahantiff)
- Charlie Hoyt (Harvard Medical School; @cthoyt)
- Thomas Liener (Pistoia Alliance)
- Harshad Hegde (LBL)
Contributors
- Alasdair Gray
- Alex Wagner
- Amelia L. Hoyt
- Andrew Williams
- Anne Thessen
- Benjamin M. Gyori
- Bill Baumgartner
- Christopher Chute
- Chris T. Evelo
- Damion Dooley
- Davera Gabriel
- Harold Solbrig
- HyeongSik Kim
- Ian Harrow
- James Malone
- James Overton
- James P. Balhoff
- James Stevenson
- Jiao Dahzi
- Joe Flack
- Jooho Lee
- Julie McMurry
- Kori Kuzma
- Kristin Kostka
- Lauren Chan
- Melissa Haendel
- Monica Munoz-Torres
- Nicole Vasilevsky
- Nomi Harris
- NĂºria Queralt-Rosinach
- Sabrina Toro
- Sebastian Koehler
- Shahim Essaid
- Sierra Moxon
- Sue Bello
- Tim Putman
Acknowledgements
Funding
Phenomics First
Parts of this work were funded by Phenomics First (NIH / NHGRI #1RM1HG010860-01):
- design of the specification;
- integration of
sssom-py
into Mondo; - development of the
sssom-py
command-line interface.
Bosch Gift to LBNL
Parts of this work were funded by a gift from Bosch to the Lawrence Berkely National Laboratories (LBNL):
sssom-py
:- IO functionality,
- file format converters,
- testing framework,
- deployment on the Python Package Index;
- SSSOM documentation (this document).
Significant contributions
- The Link Model Language (LinkML) project (used to define the data model).
- Harvard Medical School (through significant contributions of Charlie Hoyt, including refactoring of sssom-py, release and quality control infrastructure).