Dear All, I am using GOSemSim package to calculate semantic similarity of genes within a cluster, for all clusters derived from a clustering algorithm. I use the mgeneSim function to carry out these calculations. The function works fine for GO.MF and GO.CC ontologies but it seems to fail for GO.BP. When given a list of Entrez identifiers, the function seems to be stuck for a long time, thus requiring the R session to be terminated. No warning or error messages are produced. I don't seem to understand this behaviour of this function for GO.BP.. What could be wrong here? I would appreciate any help in this regard. Thanks a lot in advance. Please find attached sample Entrez IDs used for the calculation and my R session info. -- output of sessionInfo(): Entrez ids = 1132,1147,1326,1540,1654,1831,1917,2058,2289,3301,3305,33 10,3312,3313,3320,3326,3376,3476,3551,4790,4791,4792,4793,4794,5151,54 95,5537,5646,5917,5966,5970,5971,5977,6885,7098,7128,7132,7185,7278,77 63,8517,8518,8717,8737,8767,8915,9020,9253,9532,9701,9755,10010,10293, 10318,10382,10454,10758,10848,10892,11035,11140,22870,23085,23118,2324 3,23291,23474,26133,26610,28511,28512,29110,29775,54765,55140,55250,55 291,55728,57805,64170,64332,64343,79092,79155,81030,84433,89891,92609, 113457,136319,148022,150684,203068,257397,347733,387521,387522 OS -- opensuse 12.1 > sessionInfo() R version 2.15.1 (2012-06-22) Platform: x86_64-unknown-linux-gnu (64-bit) locale: [1] LC_CTYPE=en_GB.UTF-8 LC_NUMERIC=C LC_TIME=en_GB.UTF-8 LC_COLLATE=en_GB.UTF-8 [5] LC_MONETARY=en_GB.UTF-8 LC_MESSAGES=en_GB.UTF-8 LC_PAPER=C LC_NAME=C [9] LC_ADDRESS=C LC_TELEPHONE=C LC_MEASUREMENT=en_GB.UTF-8 LC_IDENTIFICATION=C attached base packages: [1] stats graphics grDevices utils datasets methods base other attached packages: [1] org.Hs.eg.db_2.7.1 igraph_0.6-2 GOSemSim_1.14.0 BiocInstaller_1.4.7 AnnotationDbi_1.18.1 [6] Biobase_2.16.0 BiocGenerics_0.2.0 RSQLite_0.11.1 DBI_0.2-5 loaded via a namespace (and not attached): [1] GO.db_2.7.1 IRanges_1.14.4 stats4_2.15.1 tools_2.15.1 -- Sent via the guest posting facility at bioconductor.org.