eduKateSG · Why Science?
Build a shared disease vocabulary across communities—without flattening meaningful differences or replacing the specialist sources that created the evidence
Choose the closest route, then return to the full index whenever you need the wider evidence chain.
Science learning becomes powerful when students can tell a measured pattern from a model, a statistical decision from a mechanism, and a useful lead from a finished conclusion. The Mondo Disease Ontology is a community-driven, open resource that harmonises disease concepts and mappings from multiple terminologies. Its official site says the project aims to harmonise disease definitions across the world; its download page publishes releases under CC BY 4.0. Mondo identifiers, labels, synonyms, relationships and cross-references can make data from different communities easier to connect. Harmonisation does not make every source concept identical, and specialist resources remain authoritative for their own scope, evidence and curation policies. This guide supports Primary Science, PSLE Science, Secondary Science, O-Level Science and STEM education as a longform evidence-reading route; it is not medical advice, a laboratory protocol, an admission promise or a career guarantee.
Related eduKate reading: ORDO and structured rare-disease concepts; Monarch Initiative phenotype–gene–disease evidence; ClinGen gene–disease validity evidence; Science Learning Hub; Education Hub; STEM Education; Careers by Subject Capability.
Primary and official sources checked on 12 October 2026: Official Mondo Disease Ontology; Official Mondo source catalogue; Official Mondo download and licence page; Mondo: Integrating Disease Terminology Across Communities; 2026 Singapore–Cambridge O-Level Biology syllabus; MOE G2/G3 Lower Secondary Science teaching and learning syllabus; 2026 MOE G2 Computing syllabus. Resource interfaces and recommendations can change, so preserve the release, access date and documentation used.
| Stage | Question | Evidence | Responsible output |
|---|---|---|---|
| Collect | Which source concepts describe disease? | Curated terminologies, identifiers and definitions | A provenance-rich source set |
| Reconcile | Which concepts are equivalent, broader, narrower or distinct? | Mappings, expert review and logical structure | A harmonised concept model |
| Publish | How can people and software use the result? | Mondo IDs, labels, synonyms, relationships and releases | A versioned open ontology |
| Maintain | What changed and what still belongs to the source authority? | Release notes, obsolete terms and source updates | A traceable, bounded integration |
Inside this guide
1–12 · Foundations and design
- 1. Start with the vocabulary problem
- 2. Understand Mondo’s purpose
- 3. Treat Mondo as community-driven
- 4. Use stable Mondo identifiers
- 5. Read labels as human-facing names
- 6. Use synonyms for discovery
- 7. Read definitions and provenance
- 8. Understand cross-references
- 9. Distinguish equivalence from similarity
- 10. Read the hierarchy
- 11. Use logical definitions carefully
- 12. Respect source authority
13–24 · Models and estimation
- 13. Track obsolete concepts
- 14. Handle merges cautiously
- 15. Handle splits and refinements
- 16. Read release dates
- 17. Use the official downloads
- 18. Validate identifiers after updates
- 19. Connect Mondo with HPO
- 20. Connect Mondo with ORDO
- 21. Connect Mondo with Monarch
- 22. Connect Mondo with ClinGen
- 23. Avoid label-only joins
- 24. Avoid circular evidence
25–36 · Diagnostics and interpretation
- 25. Represent uncertainty
- 26. Contribute corrections responsibly
- 27. Use bounded clinical language
- 28. Connect to Primary Science
- 29. Connect to Secondary Science
- 30. Connect to mathematics
- 31. Connect to computing
- 32. Connect to pathways
- 33. Did you know?
- 34. Write a reader-ready mapping report
- 35. Build a validation ladder
- 36. Finish with a reproducible bundle
Section 1 of 36
1. Start with the vocabulary problem
Different clinical, research and advocacy communities may use different identifiers or boundaries for related disease concepts.
Working checkpoint — Mondo Disease Ontology: Write the integration question before choosing a preferred label. Keep Mondo and source identifiers, mapping relations, releases and review decisions together.
For a classroom model, use animals, foods or imaginary categories before disease terms.
Section 2 of 36
2. Understand Mondo’s purpose
Mondo aims to harmonise disease definitions and terminology across sources so concepts can be connected computationally.
Working checkpoint — disease concept: Use harmonisation to link evidence, not to erase source context. Read every label or hierarchy path beside its definition, provenance and source scope.
For future study, connect ontology work to biology, language, graphs and software while checking official pathways separately.
Section 3 of 36
3. Treat Mondo as community-driven
The 2026 Mondo paper describes a community-driven, open-source approach to integrating disease terminology across communities.
Working checkpoint — cross-reference: Record contribution and review provenance for important mappings. Preserve obsolete concepts and unresolved mappings; a harmonised list is not a complete history.
For scientific writing, cite the Mondo release and the authoritative source behind a mapped claim.
Section 4 of 36
4. Use stable Mondo identifiers
A Mondo ID gives an integrated concept a stable reference even when labels or synonyms evolve.
Working checkpoint — synonym: Store the identifier and release, not the label alone. Separate ontology integration from clinical criteria, diagnosis and evidence curation.
For students, ask whether two names are truly equivalent or merely related.
Section 5 of 36
5. Read labels as human-facing names
The preferred label helps people read a record, but it is not the full definition and may change as terminology improves.
Working checkpoint — hierarchy: Display ID, label and definition together. Treat identifiers, mapping scopes and release dates as scientific data: a silent change can merge distinct concepts.
For parents, ask which specialist source supports the definition or criterion being used.
Section 6 of 36
6. Use synonyms for discovery
Exact, related, broad or narrow synonyms can improve search and text matching when their scopes are preserved.
Working checkpoint — mapping provenance: Do not treat every synonym as interchangeable in every context. Keep Mondo and source identifiers, mapping relations, releases and review decisions together.
For a classroom model, use animals, foods or imaginary categories before disease terms.
Section 7 of 36
7. Read definitions and provenance
Definitions may be supplied, adapted or cross-referenced from contributing sources.
Working checkpoint — Mondo Disease Ontology: Follow the definition source before quoting it as authority. Read every label or hierarchy path beside its definition, provenance and source scope.
For future study, connect ontology work to biology, language, graphs and software while checking official pathways separately.
Section 8 of 36
8. Understand cross-references
Cross-references connect a Mondo concept with records in other terminologies. A cross-reference is a mapped relationship, not proof that every field matches.
Working checkpoint — disease concept: Inspect mapping scope and source release. Preserve obsolete concepts and unresolved mappings; a harmonised list is not a complete history.
For scientific writing, cite the Mondo release and the authoritative source behind a mapped claim.
Section 9 of 36
9. Distinguish equivalence from similarity
Two records can overlap strongly yet differ in diagnostic criteria, mechanism, population or source purpose.
Working checkpoint — cross-reference: Use the documented mapping relation instead of inventing equivalence. Separate ontology integration from clinical criteria, diagnosis and evidence curation.
For students, ask whether two names are truly equivalent or merely related.
Section 10 of 36
10. Read the hierarchy
Parent and child relationships support navigation and reasoning across broader and narrower disease classes.
Working checkpoint — synonym: Do not assume every child inherits every informal statement about its parent. Treat identifiers, mapping scopes and release dates as scientific data: a silent change can merge distinct concepts.
For parents, ask which specialist source supports the definition or criterion being used.
Section 11 of 36
11. Use logical definitions carefully
Axioms can connect disease concepts with anatomy, phenotype, cause or other ontology classes to support automated reasoning.
Working checkpoint — hierarchy: Open the actual axiom before explaining an inferred relation. Keep Mondo and source identifiers, mapping relations, releases and review decisions together.
For a classroom model, use animals, foods or imaginary categories before disease terms.
Section 12 of 36
12. Respect source authority
Mondo’s rare-disease guidance notes that authoritative sources remain the source of truth for their own content.
Working checkpoint — mapping provenance: Link back to the specialist source for criteria and evidence. Read every label or hierarchy path beside its definition, provenance and source scope.
For future study, connect ontology work to biology, language, graphs and software while checking official pathways separately.
Section 13 of 36
13. Track obsolete concepts
A concept may be retired when it is duplicated, merged, replaced or no longer supported. Old data still need a traceable route forward.
Working checkpoint — Mondo Disease Ontology: Follow replacement annotations rather than deleting history. Preserve obsolete concepts and unresolved mappings; a harmonised list is not a complete history.
For scientific writing, cite the Mondo release and the authoritative source behind a mapped claim.
Section 14 of 36
14. Handle merges cautiously
A merge can simplify integration, but local records may have used the older concepts with distinctions that matter.
Working checkpoint — disease concept: Review affected data before remapping automatically. Separate ontology integration from clinical criteria, diagnosis and evidence curation.
For students, ask whether two names are truly equivalent or merely related.
Section 15 of 36
15. Handle splits and refinements
New evidence can divide a broad historical concept into more precise entities.
Working checkpoint — cross-reference: Preserve the original assertion and migration decision. Treat identifiers, mapping scopes and release dates as scientific data: a silent change can merge distinct concepts.
For parents, ask which specialist source supports the definition or criterion being used.
Section 16 of 36
16. Read release dates
Mondo publishes versioned releases; external services can update later than the main release.
Working checkpoint — synonym: Record the source URL, release and retrieval date. Keep Mondo and source identifiers, mapping relations, releases and review decisions together.
For a classroom model, use animals, foods or imaginary categories before disease terms.
Section 17 of 36
17. Use the official downloads
The download page offers ontology products and states a CC BY 4.0 licence. Different serialisations serve different tools.
Working checkpoint — hierarchy: Choose the documented product and retain attribution. Read every label or hierarchy path beside its definition, provenance and source scope.
For future study, connect ontology work to biology, language, graphs and software while checking official pathways separately.
Section 18 of 36
18. Validate identifiers after updates
An identifier can remain valid while its label, parents, mappings or status change.
Working checkpoint — mapping provenance: Diff the concepts used by a project at every upgrade. Preserve obsolete concepts and unresolved mappings; a harmonised list is not a complete history.
For scientific writing, cite the Mondo release and the authoritative source behind a mapped claim.
Section 19 of 36
19. Connect Mondo with HPO
Disease concepts and phenotype terms answer different questions: one identifies a disease entity, the other describes observed features.
Working checkpoint — Mondo Disease Ontology: Keep diagnosis and phenotype fields separate. Separate ontology integration from clinical criteria, diagnosis and evidence curation.
For students, ask whether two names are truly equivalent or merely related.
Section 20 of 36
20. Connect Mondo with ORDO
Mondo can map to ORDO and other rare-disease resources, but ORDO carries its own scope and expert curation.
Working checkpoint — disease concept: Retain the ORDO identifier when its provenance matters. Treat identifiers, mapping scopes and release dates as scientific data: a silent change can merge distinct concepts.
For parents, ask which specialist source supports the definition or criterion being used.
Section 21 of 36
21. Connect Mondo with Monarch
Monarch uses integrated ontologies and knowledge graphs to connect diseases, genes, variants and phenotypes.
Working checkpoint — cross-reference: Open the underlying evidence edge, not only the graph path. Keep Mondo and source identifiers, mapping relations, releases and review decisions together.
For a classroom model, use animals, foods or imaginary categories before disease terms.
Section 22 of 36
22. Connect Mondo with ClinGen
Gene–disease validity curation depends on the exact disease entity and inheritance mechanism.
Working checkpoint — synonym: Check the precise ClinGen record and current classification. Read every label or hierarchy path beside its definition, provenance and source scope.
For future study, connect ontology work to biology, language, graphs and software while checking official pathways separately.
Section 23 of 36
23. Avoid label-only joins
Matching text alone can merge homonyms, historical names or distinct subtypes.
Working checkpoint — hierarchy: Join on identifiers and reviewed mappings. Preserve obsolete concepts and unresolved mappings; a harmonised list is not a complete history.
For scientific writing, cite the Mondo release and the authoritative source behind a mapped claim.
Section 24 of 36
24. Avoid circular evidence
Several databases may repeat the same original assertion through cross-references, making one source look like many.
Working checkpoint — mapping provenance: Trace claims to primary provenance. Separate ontology integration from clinical criteria, diagnosis and evidence curation.
For students, ask whether two names are truly equivalent or merely related.
Section 25 of 36
25. Represent uncertainty
Some mappings or classifications remain contested or under review.
Working checkpoint — Mondo Disease Ontology: Expose uncertainty rather than forcing a definitive one-to-one map. Treat identifiers, mapping scopes and release dates as scientific data: a silent change can merge distinct concepts.
For parents, ask which specialist source supports the definition or criterion being used.
Section 26 of 36
26. Contribute corrections responsibly
Community issue trackers and curation workflows let users propose changes with evidence.
Working checkpoint — disease concept: Submit a reproducible example and source citation. Keep Mondo and source identifiers, mapping relations, releases and review decisions together.
For a classroom model, use animals, foods or imaginary categories before disease terms.
Section 27 of 36
27. Use bounded clinical language
An ontology supports representation and integration; it does not diagnose a person or set clinical criteria by itself.
Working checkpoint — cross-reference: Refer to current clinical guidance and specialist review. Read every label or hierarchy path beside its definition, provenance and source scope.
For future study, connect ontology work to biology, language, graphs and software while checking official pathways separately.
Section 28 of 36
28. Connect to Primary Science
A fictional card-sort can show how one object has a preferred name, nicknames and membership in broader groups.
Working checkpoint — synonym: Use everyday examples before discussing disease terminology. Preserve obsolete concepts and unresolved mappings; a harmonised list is not a complete history.
For scientific writing, cite the Mondo release and the authoritative source behind a mapped claim.
Section 29 of 36
29. Connect to Secondary Science
Classification, inheritance and biological variation show why categories change as evidence improves.
Working checkpoint — hierarchy: Separate an observed feature from a named disease concept. Separate ontology integration from clinical criteria, diagnosis and evidence curation.
For students, ask whether two names are truly equivalent or merely related.
Section 30 of 36
30. Connect to mathematics
Set overlap, hierarchy and graph paths show why similarity is not the same as equality.
Working checkpoint — mapping provenance: Draw a toy concept map and test transitive assumptions. Treat identifiers, mapping scopes and release dates as scientific data: a silent change can merge distinct concepts.
For parents, ask which specialist source supports the definition or criterion being used.
Section 31 of 36
31. Connect to computing
Ontologies, identifiers, graph reasoning, version control and automated quality checks turn vocabulary into infrastructure.
Working checkpoint — Mondo Disease Ontology: Write migration tests for obsolete and merged IDs. Keep Mondo and source identifiers, mapping relations, releases and review decisions together.
For a classroom model, use animals, foods or imaginary categories before disease terms.
Section 32 of 36
32. Connect to pathways
Disease ontology work links biology, medicine, language, software and data stewardship and can illuminate STEM pathways.
Working checkpoint — disease concept: Check official education and professional requirements separately. Read every label or hierarchy path beside its definition, provenance and source scope.
For future study, connect ontology work to biology, language, graphs and software while checking official pathways separately.
Section 33 of 36
33. Did you know?
Mondo is not simply a list of names: it publishes identifiers, relationships, mappings and logical structures designed for computation.
Working checkpoint — cross-reference: Inspect provenance before following an inferred connection. Preserve obsolete concepts and unresolved mappings; a harmonised list is not a complete history.
For scientific writing, cite the Mondo release and the authoritative source behind a mapped claim.
Section 34 of 36
34. Write a reader-ready mapping report
Name the Mondo release, source terminologies, mapping relations, unresolved conflicts, obsolete concepts, licence and intended use.
Working checkpoint — synonym: Keep source authority visible. Separate ontology integration from clinical criteria, diagnosis and evidence curation.
For students, ask whether two names are truly equivalent or merely related.
Section 35 of 36
35. Build a validation ladder
Validate IDs, review labels and definitions, inspect mapping scope, test hierarchy inferences, then confirm with specialist sources.
Working checkpoint — hierarchy: Challenge the most consequential equivalence first. Treat identifiers, mapping scopes and release dates as scientific data: a silent change can merge distinct concepts.
For parents, ask which specialist source supports the definition or criterion being used.
Section 36 of 36
36. Finish with a reproducible bundle
Deliver the ontology release, selected concepts, source IDs, mapping table, change report, scripts, tests, licences and review notes.
Working checkpoint — mapping provenance: Make every harmonisation decision traceable. Keep Mondo and source identifiers, mapping relations, releases and review decisions together.
For a classroom model, use animals, foods or imaginary categories before disease terms.
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