An evaluation of linear RNA amplification in cDNA microarray gene expression analysis

DNA microarray is becoming a common tool across a broad range of disciplines, particularly in the basic and clinical biomedical sciences. However, the limitation of this technology is the requirement for relatively large amount of RNA for labeling and hybridization. T7-based linear amplification technique can overcome this limitation and enables consumption of very low amount of samples. In this study, we utilized a low RNA input fluorescent linear amplification kit from Agilent to amplify 0.2 μg total RNA and compared the gene expression profiles generated from amplified aRNA and total RNA. Our results demonstrated that nanograms total RNA can be amplified reproducibly with this protocol and can generate gene expression profiles comparable with unamplified total RNA. Furthermore, quantitative real-time PCR measurements of a set of 10 genes showed good correlation with amplified aRNA arrays.