RNA integrity number (RIN) - towards standardization of RNA quality assessment

1649 RNA quality assessment has been identified as one of the most critical elements in order to obtain meaningful gene expression data via microarray or real-time PCR experiments. Current advances in microfluidics have improved RNA quality measurements tremendously by allowing a more detailed look at RNA degradation patterns by providing electrophoretic traces of RNA samples. However, the interpretation of such electropherograms still requires a certain level of experience and can vary from one researcher to the next. A so-called “RNA integrity number” (RIN) algorithm is introduced that assigns a user-independent integrity number to each RNA sample. The RIN has been developed using neural networks by “teaching” this algorithm with a large number of RNA integrity data. It was found that the RIN is more reliable than the ribosomal ratio, when assessing the integrity of RNA samples. The RIN is shown to be largely independent of RNA concentration, instrument (Agilent 2100 bioanalyzer), and most importantly, the origin of the RNA sample. Using the RIN, researchers can work towards standardization of the important RNA integrity measurement ensuring reproducibility and reliability of gene expression experiments.