Hi, I don't know if this is by accident or design, but some code I had working with GenomeGraphs 1.2.3 is now failing under version 1.4.0. I've reduced the problem to the following test case: > require('biomaRt') > require('GenomeGraphs') > mart <- useDataset('hsapiens_gene_ensembl', useMart('ensembl')) > genesminus <- makeGeneRegion(start = 10662805, end = 10718158, strand = "-", chromosome=12, biomart=mart) > genesplus <- makeGeneRegion(start = 10662805, end = 10718158, strand = "+", chromosome=12, biomart=mart) > gdPlot(list('minus strand'=genesminus, 'plus strand'=genesplus)) This draws the minus strand just fine, but the plus strand (which, I think crucially, retrieves no genes) fails with the following message: "Error in if (ens[1, 6] == 1) { : missing value where TRUE/FALSE needed" I know that the same code running under R 2.8.1/BioC 2.3/GenomeGraphs 1.2.3 draws both strands without complaining. Is this change to GenomeGraphs behaviour intentional, or can this be considered a bug? Many thanks, Tim > sessionInfo() R version 2.9.0 (2009-04-17) x86_64-apple-darwin9.6.0 locale: en_GB.UTF-8/en_GB.UTF-8/C/C/en_GB.UTF-8/en_GB.UTF-8 attached base packages: [1] grid stats graphics grDevices utils datasets methods [8] base other attached packages: [1] GenomeGraphs_1.4.0 biomaRt_2.0.0 loaded via a namespace (and not attached): [1] RCurl_0.94-1 XML_2.3-0