assertion  retraction  graph  subject       predicate        object     datatype    annotation
1          0           graph  DOID:0050458  rdfs:subClassOf  DOID:4972  _IRI        
1          0           graph  DOID:0060597  rdfs:subClassOf  DOID:4972  _IRI        
1          0           graph  DOID:4972     oio:id           DOID:4972  xsd:string