By default pathview sum up the gene (or compound etc) data mapped to one node, which works well in common conditions. But you may specify other methods, like taking mean, median, max etc of these mapped gene data. Check the help information within R with the following lines: library(pathview) ?pathview And look on argument node.sum. page 6 of the pathview vignette gives more info on this. Weijun -------------------------------------------- On Mon, 8/5/13, timmy26 wrote: Subject: pathview, when multiple entrzgene ids were mapper to the same node in kegg pathway Date: Monday, August 5, 2013, 2:51 AM Dear Dr LuoCould you please tell me how pathview decide the color of a node when multiple gene ids in the query list could be mapped to that node?Thanks in advance!?Best wishes!?