Which type of mutation results in a string of altered amino acids at the end of the polypeptide product?

Frameshift

Explanation:

A frameshift mutation is a type of genetic mutation that results from the abnormal deletions or insertions of nucleotide bases in a DNA sequence which is not divisible by three. The deletions or insertions of the nucleotide bases can either reduce or increase the length of DNA sequence respectively, hence altering the reading frame. The change in the length of the DNA sequence drastically alters the mRNA and hence the final protein produced.

An example of a disorder caused by frameshift mutation is the Tay-Sachs disease. The frameshift mutation in this disorder result in the deficiency of an important enzyme called hexosaminidase A which plays an important role in the central nervous system.