The following DataNodes have no identifier: 1
http://classic.wikipathways.org/instance/WP1560_r116839 http://rdf.wikipathways.org/Pathway/WP1560_r116839/DataNode/c3a5b (Calmodulin)
More details at https://www.wikipathways.org/WikiPathwaysCurator/DataNodesTests/dataNodesWithoutIdentifier