assertion  retraction  graph  subject    predicate        object     datatype    annotation
1          0           graph  DOID:2519  rdfs:subClassOf  DOID:2277  _IRI        
1          0           graph  DOID:2277  oio:id           DOID:2277  xsd:string  
1          0           graph  DOID:1100  rdfs:subClassOf  DOID:2277  _IRI