[BioC] Affymetrix annotation package

[Hans-Ulrich Klein]

Dear list,

I wonder about the annotation of some probesets on Affymetrix chips. E.g.:

> library("hgu95av2")
> get("1726_at", env=hgu95av2ACCNUM)
[1] "HG919-HT919"

Is "HG919-HT919" really an accession number? I do not get any hits at NCBI's GenBank. NetAffx gives the same identifier for that probeset, but in a field called "Representative Public ID".
There are some more probesets with "HGXXX-HTXXX" as ACCNUM on the hgu95av2 chip. Where can get more information about this identifiers?

Thanks,
Hans-Ulrich