assertion  retraction  graph  subject    predicate        object     datatype    annotation
1          0           graph  DOID:6160  rdfs:subClassOf  DOID:5551  _IRI        
1          0           graph  DOID:5551  oio:id           DOID:5551  xsd:string  
1          0           graph  DOID:6693  rdfs:subClassOf  DOID:5551  _IRI