Hi Alejandro, Currently, pathview does not take EC number as in put. But you may convert EC to KEGG or Entrez Gene ID using KEGGREST package. Then use mol.sum in pathview packge to map the EC based data to Gene ID based data. For example: library(KEGGREST) hsa.ec <- keggLink("enzyme", "hsa") headhsa.ec) ? pathview::mol.sum HTH, Weijun -------------------------------------------- On Wed, 9/25/13, Alejandro wrote: Subject: Pathview question Date: Wednesday, September 25, 2013, 11:40 AM Hi Im interested in using your pathview package, but I would like to use it using EC number as input. is this possible? thanks -- Alejandro