Abstract
RNA editing, or post-transcriptional changes in the sequences of RNAs, is being increasingly recognized as an important player in the regulation of gene expression in vertebrates and invertebrates. Different types of RNA editing have been reported. This review discuss the type of RNA editing caused by cellular enzymes known as adenosine deaminases that act on RNAs (ADARs), and it's significance in the lifecycle of an RNA virus, hepatitis delta virus.