it occurs when a base pair is deleted from a sequence.it is the opposite of insertion mutation.These two types of point mutation are grouped together because both of them can drastically affect the sequence of amino produced. With one or two based added or deleted, all of the three - base condom change . <u>This is called a frame shift</u><u>.</u> e.g if a sequence of condoms in DNA is normally CCT ATG TTT and an extra A is added between the two cytosine bases, the sequence will instead react CAC TAT GTT T. This completely changed the amino acids that would be produced, which in turn changes the structure and function of the resulting protein and can render it useless. Similarly, if one base was deleted, the sequence would also shift.
