assertion  retraction  graph  subject    predicate        object     datatype    annotation
1          0           graph  DOID:5538  rdfs:subClassOf  DOID:4288  _IRI        
1          0           graph  DOID:4288  oio:id           DOID:4288  xsd:string  
1          0           graph  DOID:4287  rdfs:subClassOf  DOID:4288  _IRI