RNA spike-in (original) (raw)

An RNA spike-in is an RNA transcript of known sequence and quantity used to calibrate measurements in RNA hybridization assays, such as DNA microarray experiments, RT-qPCR, and RNA-Seq. A spike-in is designed to bind to a DNA molecule with a matching sequence, known as a control probe. This process of specific binding is called hybridization. A known quantity of RNA spike-in is mixed with the experiment sample during preparation. The degree of hybridization between the spike-ins and the control probes is used to normalize the hybridization measurements of the sample RNA.