QC and normalisation of microarray experiments - BiGCaT

Intermezzo: custom CDF files
• Affymetrix provides annotations files for their probesets (CDF file)
• When these get outdated, one can of course update probeset
annotations
• But it may be even better to disassemble these sets into the separate
probes, reannotate probes, and assemble into new probesets
(different ones)
• This is exactly what custom CDF files do
• Note that reassembled probesets do not contain the same number
of probes anymore
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