Like-like hybridization to test 7K3 platform variability

This experiment compared separate pools of Drosophila which received identical topical treatments of 99% ethanol 6 hours after exposure. The purpose of this was to assess the degree of natural variability that could be expected to be observed between samples in the absence of distince treatments. This was to allow for greater confidence in interpreting the results of other experiments which compared insects that received different treatments. It was found that a differential expression log2ratio range of -1.41 to 1.41 encompassed over 99% of all genes in this experiment. Keywords: platform background variation evaluation 8 microarray chips were hybridized with RNA extracted from Drosophila treated with ethanol. There were four biological replicates and four dye-reversal replicates.