The following DataNodes have no identifier: 1
http://classic.wikipathways.org/instance/WP3893_r129335 http://rdf.wikipathways.org/Pathway/WP3893_r129335/DataNode/ab627 (ROR-gammat)
More details at https://www.wikipathways.org/WikiPathwaysCurator/DataNodesTests/dataNodesWithoutIdentifier