New protocol in spotting microarray technique.

The "spotting" microarray technique, consisting in large sets of DNA sequences spotted on poly-L-lysine-coated glass microscope slides, has been developed to comparatively analyze genome-wide patterns of mRNA expression. It is now a valuable tool employed in order to quantitatively monitor gene expression profiles, as well as to analyze the alterations produced in case of genetic diseases, or induced by different treatments, abnormal nutrition and toxin. Our group improved the standard protocol as well as the results spreadsheet, adding new experiments and mathematical processing procedures in order to increase the accuracy of the data and get new information. In this contribution, we propose and verify two procedures to correct the spot ratios and a new protocol to get the normal variability of the digital gene expression.