Hi there, I make custom CDF files for use with our Affy tiling arrays. Each one I make by aligning the oligos to the latest genome build and then intersecting the coordinates with the latest GFF annotation files. This works fine with applications that can accept CDF files but I would like to use Bioconductor to condense expression values. It would also be nice if there was an easy way to link in things like GO terms etc that are usually available from the genome repositories. Could you tell me how the CDF repositories are made for Bioconductor and if some scripts exist for automating this process. Any ideas? Thanks Edward Oakeley FMI, Basel