The following DataNodes have no identifier: 1
http://classic.wikipathways.org/instance/WP1064_r117573 http://rdf.wikipathways.org/Pathway/WP1064_r117573/DataNode/aef70 (PIK3R2)
More details at https://www.wikipathways.org/WikiPathwaysCurator/DataNodesTests/dataNodesWithoutIdentifier