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. All the other amino acids and their position are exactly the same or is exactly the same. So whenever an insertion or a deletion takes place in multiples of three, this does not lead to a shift in the reading frame. And such mutations are known as non frame shift mutations because all the amino acids that would be produced if there was no mutation are still produced.