Validation of Array Data
Elisa Wurmbach
from: Real-Time PCR: Current Technology and Applications (Edited by: Julie Logan, Kirstin Edwards and Nick Saunders). Caister Academic Press, U.K. (2009)
Abstract
Microarray techniques allow the parallel assessment of the relative expression of thousands of transcripts in response to different experimental conditions or in different tissues. The ability to correctly identify differentially expressed genes is limited by the signal to noise ratio, the variation in the levels of gene expression, and/or the variability in the measurements due to the assay itself. Therefore, an unequivocal identification of differentially expressed transcripts requires independent confirmation. Quantitative real-time RT-PCR (qPCR) is the method of choice because of its broad range of linearity. Furthermore, it can be easily adapted to systematically study tens to hundreds of different transcripts. The cDNA microarray technique is introduced as an example, followed by comparisons to different microarray platforms and their characteristics. Data analysis of microarray experiments will show the importance of verification of results. General differences between microarray hybridisations and PCR reactions and, in particular, the performance of different platforms are described and compared. Furthermore, the effects of increasing tissue complexity on detection of differentially expressed transcripts are elucidated with specific examples read more ...
