Normal DNA sequence: (enzyme lysozyme)
TAG-TTT-TCA-GGT-AGT-GAA-TTA-CGA
The mutuation is of 'insertion' type; e.g. add T at the beginning:
TTA-GTT-TTC-AGG-TAG-TGA-ATT-ACG-A
The new sequence gives a completely different chain of a.a. And this is a dysfunctional protein.
PS: you can use your book to write the name of these a.a.s below the letters.