Disease Ontology

What is Disease Ontology?

The Mondo Disease Ontology aims to harmonize disease definitions across the world. Learn more about Mondo DO.

Currently, various resources describing diseases use many different definitions - sometimes these definitions overlap and sometimes they conflict. This makes mappings information from these sources incomplete, inconsistent, and inaccurate. The Mondo Disease Ontology, was created to provide a unified, logic-based classification for diseases definitions. It describes the individual phenotypic features that constitute a disease. Development of the Mondo Disease Ontology is coordinated with the Human Phenotype Ontology (HPO) and provides a hierarchical structure for classification or “rolling up” of diseases to higher level groupings. It provides mappings to other disease resources, so that we know when two disease names or identifiers are equivalent.

The disease definitions from MONDO have been mapped to UniProt sequences by the Knowledge Management Center (KMC) for the Illuminating the Druggable Genome (IDG) program and are available for PDB entities mapped to UniProt.

Why Browse by Disease Ontology?

The Disease Ontology browser allows users to identify and explore the structures of polymer entities that are associated with/impacted by specific diseases. The structures of these protein entities may be examined independently or grouped together to see if there are any common features or trends in these proteins to provide new insights about the disease.

How to use the Disease Ontology Browser ?

The Disease Ontology browser allows users to type in a disease name, browse through a series of disease terms to select ones that are of interes, or enter a 7 digit MONDO ID in the search box to identify the corresponding PDB entities.

After locating the disease term of interest in the browser, users can view the number of polymers in this group. Clicking on the numbers listed next to the component name will launch a search for all polymer entities in the PDB that are associated with it.


Browse the PDB archive for entities that are associated with Lynch Syndrome (an inherited genetic disorder linked to an increased risk of developing cancer) as follows:

  • Type the name of a disease of interest in the search box on the page e.g., "lynch syndrome" and select from the options "Lynch syndrome (MONDO:0005835" OR
  • Type the 7 digit MONDO ID "0005835". If you begin typing the ID 5835, in the search box on the top of the page, autocomplete suggestions will appear, from which you can select the appropriate options to search through the browser tree.

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Last updated: 6/25/2024