sfalcon at fhcrc.org
Thu Jul 13 22:02:07 CEST 2006
jmungal at berkeley.edu writes:
> Hello, I am an undergraduate doing summer research at Stanford University.
> I've downloaded a few GSP files from GEO and converted them to the class
> exprSet. Typically with an object of class exprSet you can simply type
> and it R will give you the annotation key for the corresponding LocusLink
I'm not so sure about that. The annotation() method for the exprSet
class is AFAIK a simple accessor for the annotation slot of said
class. This slot is intended to hold a string naming the annotation
package appropriate for the data contained in the exprSet.
> However, with the data sets I have, there is no annotation. Does
> anyone know an easy way of finding the LocusLink ID's for such a
> data set?
The probe ID ==> EntrezGene ID mapping is chip dependent. For
many Affymetrix chips, there is a BioC annotationd data package
available. That is not the case for two-color chips.
More information about the Bioconductor