Hi@all, I apologize in advance if this is a trivial question, I’m not very experienced with graphs. First, I have a hierarchical order of a disease list. Just for example: 1. Respiratory system disease 1.1. Asphyxia neonatorum 1.2. Croup 1.3. Lower respiratory tract disease 1.4. Bronchial disease 1.4.1. asthma <http://bioportal.bioontology.org/ontologies/DOID/?p=classes&conceptid=http%3A%2F%2Fpurl.obolibrary.org%2Fobo%2FDOID_2841> 1.4.2. bronchiectasis 1.4.3. bronchitis 1.5. lung disease 1.5.1. acute chest syndrome 1.5.2. bronchiolitis 1.5.3. brown induration 1.6. interstitial lung disease 1.6.1. bronchiolitis obliterans 1.6.2. extrinsic allergic alveolitis 1.6.3. pneumoconiosis Next, I have a database with people’s medical records. For example: Patient-1: asthma, bronchiolitis Patient-2: asthma, pneumoconiosis Lastly, when a new patient enters the system. For example: Patient-to-search: asthma, brown induration I want to find the person which is “most similar” in terms of the diseases hierarchy. (Which is Patient-1). How do I accomplish such task efficiently with the graph tool? Thanks, Dov