Overview

Spotted complementary DNA microarrays (cDNA microarrays) are a high-throughput technology that allows simultaneous monitoring of the expression levels of many genes. Each experimental comparison comprises a microarray slide and two fluorescently labelled samples. These samples are competitively hybridized to the deposited DNA on the microarray. The basic principle of a spotted cDNA microarray is that, if one sample contains more of the corresponding transcript, then the signal intensity for the dye use to label that sample should be proportionally higher than the signal intensity for the other dye.

To compare multiple samples, an experimental comparison design should be constructed, providing data that may be analyzed in various ways.