assertion  retraction  graph  subject       predicate        object     datatype    annotation
1          0           graph  DOID:0050898  rdfs:subClassOf  DOID:2602  _IRI        
1          0           graph  DOID:3813     rdfs:subClassOf  DOID:2602  _IRI        
1          0           graph  DOID:2602     oio:id           DOID:2602  xsd:string  
1          0           graph  DOID:2601     rdfs:subClassOf  DOID:2602  _IRI