I am trying to adapt the limma-package volcanoplot so that the user can specify a list of genesymbols that get labeled in the plot. To do this, I have to convert from genesymbol to affy_ID, to find the right spot in the fit object. Is there a function to convert from genesymbol to affy_ID? Is there another way to do this? Thanks Andreas -- -------------------------- Andreas Zankl, MD Division of Molecular Pediatrics Clinique Infantile 02/50 CHUV Avenue Pierre Decker 2 CH-1011 Lausanne Switzerland Phone: +41-21-3143778 Fax: +41-21-3143546 Email: andreas.zankl at gmail.com

Hi Andreas, You could have a look at the biomaRt package (take the version from developmental packages). You'll need the following commands: mart<-martConnect() affyID <- getFeature(symbol="P53", array="hgu95av2",mart=mart) To see which affy arrays are available do: getAffyArrays(mart) best, Steffen Andreas Zankl wrote: >I am trying to adapt the limma-package volcanoplot so that the user >can specify a list of genesymbols that get labeled in the plot. To do >this, I have to convert from genesymbol to affy_ID, to find the right >spot in the fit object. Is there a function to convert from >genesymbol to affy_ID? Is there another way to do this? > >Thanks >Andreas > >