Abstract

Studying the Diversity and “Signature” of Small RNA in Different Bodily Fluids using Next Generation Sequencing and the Impact on Biomarker Discovery

Bernard Lam, Senior Research Scientist, Norgen Biotek Corporation

In this presentation, we will discuss the impact of various steps in the Next Generation Sequencing workflow, including RNA extraction, enhancement of target signal by abundant transcript removal and library preparation, on obtaining valuable small RNA expression profile from a specific bodily fluid. The use of bodily fluids such as whole blood, plasma, serum, urine or saliva for biomarker discovery has attracted tremendous attention in recent years. However, the characteristics of RNA (and DNA) present in bodily fluids are quite different from traditional samples such as cells and tissues. First, many of the RNAs in bodily fluids are either free-circulating or are within extra-cellular vesicles such as exosomes. More importantly, the RNAs present in bodily fluids are usually of very low abundance and small in sizes. This presents challenges for detection and studies using many next-generation gene expression technologies. We will present data on the “signature” or small RNA characteristics of different bodily fluids. We will present examples, using such RNA “signature” of a bodily fluid, where removing an abundant RNA transcript can significantly improve the small RNA diversity detected by sequencing. Finally, we will discuss different RNA extraction technologies and their ability to recover microRNA with low GC contents from bodily fluids with low RNA content.