Please refer to the diagram for a schematic outline of the assay strategy. Full details of this assay can be found in the GeneChip® Expression Analysis Technical Manual.

Briefly, we recommend starting with either total RNA (minimum of 5 µg) or poly-A mRNA (minimum of 0.2 µg). The sample is reverse transcribed, using a T7-oligo(dT) primer, and double-stranded cDNA is synthesized. The double-stranded cDNA, with the incorporated T7 promoter, is then used as a template in the subsequent in vitro transcription reaction.