The following DataNodes have no identifier: 1
http://classic.wikipathways.org/instance/WP3221_r117478 http://rdf.wikipathways.org/Pathway/WP3221_r117478/DataNode/b6896 (NEMO)
More details at https://www.wikipathways.org/WikiPathwaysCurator/DataNodesTests/dataNodesWithoutIdentifier