They can arise from extremely simple mutations such as the addition or removal of a single nucleotide. Frameshift mutations do not include substitutions where a nucleotide replaces another. In substitution mutations, the polypeptide only changes by a single amino acid.

What type of mutation is substitution?

​Substitution Substitution is a type of mutation where one base pair is replaced by a different base pair. The term also refers to the replacement of one amino acid in a protein with a different amino acid.

What type of mutation is frameshift?

A frameshift mutation is a type of mutation involving the insertion or deletion of a nucleotide in which the number of deleted base pairs is not divisible by three. “Divisible by three” is important because the cell reads a gene in groups of three bases.