RNA  editing  is  the  name  given  to  several  reactions  whereby  the  nucleotide series  on an mRNA  molecule  should  be modified  by mechanisms  other  than RNA  splicing.  The Individual  nucleotides  within  the  mRNA  should  be  change  to other nucleotides,  erased entirely or additional  nucleotides  inserted. The result of RNA editing is to change the coding capacity of the mRNA so in which it encodes a variant polypeptide than which really encoded by the gene. An instance of RNA editing in humans is apolipoprotein B mRNA and in liver, the mRNA does not undergo editing and the protein produced after translation is called as apolipoprotein   B100 that shows in the figure.  In  cells  of  the  little  intestine,   RNA  editing  causes the conversion of a single C residue in the mRNA to U and in so doing,  modify  a codon  for  glutamine  (CAA)  to a termination  codon UAA.

                                                        Figure: RNA editing