assertion  retraction  graph  subject     predicate        object      datatype    annotation
1          0           graph  DOID:10816  rdfs:subClassOf  DOID:10021  _IRI        
1          0           graph  DOID:7959   rdfs:subClassOf  DOID:10021  _IRI        
1          0           graph  DOID:7479   rdfs:subClassOf  DOID:10021  _IRI        
1          0           graph  DOID:10021  oio:id           DOID:10021  xsd:string  
1          0           graph  DOID:10020  rdfs:subClassOf  DOID:10021  _IRI