Figure 1.

The Human Phenotype Ontology

The HPO term Bilateral congenital hip dislocation and all paths to the root that emanate from this term are shown. Some of the annotated disease entries from OMIM, as well as the total number of annotated diseases, are shown next to the terms. Note that because of the true-path rule, a disease that is directly annotated to a specific term is also implicitly annotated to all ancestors of that term. For instance, Ehlers Danlos syndrome type VII is directly annotated to Bilateral congenital hip dislocation and is thereby implicitly annotated to Abnormality of the hips, Dislocations, and the other terms shown in the figure.