The following DataNodes have no identifier: 2
http://classic.wikipathways.org/instance/WP1261_r108380 http://rdf.wikipathways.org/Pathway/WP1261_r108380/DataNode/def67 (P70S6K)
http://classic.wikipathways.org/instance/WP1261_r108380 http://rdf.wikipathways.org/Pathway/WP1261_r108380/DataNode/c56df (Unknown)
More details at https://www.wikipathways.org/WikiPathwaysCurator/DataNodesTests/dataNodesWithoutIdentifier