Quality Control Information from Preparation of Materials for Spotting

When either cDNA clones are spotted or specifi c regions of a genome are
selected and amplifi ed, they have to go through at least one round of PCR
before printing. It is important that quality control information about these PCR
products be tracked, because it may subsequently be useful for selection of
data from a microarray database. For example, data from spots where the PCR
failed, or the fragment was of an unexpected size, can be fi ltered out. Failed
or anomalous products are printed because PCR reactions are usually done in
96-well format, so to simply spot only the products of those reactions that were
deemed to have worked is impractical—instead, the content of each well in each
plate is spotted. Thus, tracking the quality of those products is necessary.