But in this case, what we essentially do, we do not actually shift the reading frame. What we do is we simply insert a single amino acid in this case. But all the amino acids that are produced after the inserted amino acid are exactly the same as before. So we have leucine, alanine and arginine. And we have leucine, alanine and arginine. So basically the only difference between the polypeptide chain produced in the non mutated case and in a mutated case is our single amino acid that is found between the second and third amino acid.