What type of mutation shifts the reading frame due to insertion or deletion of nucleotides?

A frameshift mutation occurs when the addition or deletion of nucleotides in a DNA sequence alters the way the sequence is read by shifting the reading frame. This is significant because the genetic code is read in triplets, or codons, each of which corresponds to a specific amino acid. When nucleotides are inserted or deleted, not only does the original codon change, but subsequent codons are also affected, potentially resulting in a completely different amino acid sequence from that point forward. This can lead to substantial functional changes in the protein that is produced, potentially resulting in diseases or malfunctions if critical proteins are altered.

The other types of mutations listed do not cause a shift in the reading frame. Point mutations involve a change in a single nucleotide, silent mutations change a nucleotide without altering the amino acid sequence, and translocation mutations involve the movement of segments of DNA between non-homologous chromosomes, but do not typically cause a direct frameshift in the reading sequence of a gene.