Background: Used alone, the MAS5.0 algorithm for generating expression summaries has been criticized for high False Positive rates resulting from exaggerated variance at low intensities. Results: Here we show, with replicated cell line data, that, when used alongside detection calls, MAS5 can be both selective and sensitive. A set of differentially expressed transcripts were identified that were found to be changing by MAS5, but unchanging by RMA and GCRMA. Subsequent analysis by real time PCR confirmed these changes. In addition, with the Latin square datasets often used to assess expression summary algorithms, filtered MAS5.0 was found to have performance approaching that of its peers. Conclusion: When used alongside detection calls, MAS5 is a sensitive and selective algorithm for identifying differentially expressed genes. Background A significant challenge with Affymetrix expression data is to provide an algorithm that combines the signals from the multiple Perfect-Match (PM) and ...
Stuart D. Pepper, Emma K. Saunders, Laura E. Edwar