The following DataNodes have no identifier: 1
http://classic.wikipathways.org/instance/WP2814_r128676 http://rdf.wikipathways.org/Pathway/WP2814_r128676/DataNode/ab9f0 (AP1)
More details at https://www.wikipathways.org/WikiPathwaysCurator/DataNodesTests/dataNodesWithoutIdentifier