Nucleic acid polyacrylamide gel electrophoresis (PAGE) has played a critical role in the identification and characterization of viroid RNAs. In addition, double PAGE has been a very efficient tool for the detection of viroids as it is sequence independent and is based on the viroid structure of covalently closed/circular molecules. sPAGE has been widely used for the identification of new viroids as well as a routine detection tool.
