The following DataNodes have no identifier: 1
http://classic.wikipathways.org/instance/WP3268_r80913 http://rdf.wikipathways.org/Pathway/WP3268_r80913/DataNode/db247 (KRAS)
More details at https://www.wikipathways.org/WikiPathwaysCurator/DataNodesTests/dataNodesWithoutIdentifier