What type of mutation involves the loss of one or more nucleotides from a DNA segment?

The type of mutation that involves the loss of one or more nucleotides from a DNA segment is a deletion. This mutation can result in a shift in the reading frame during protein synthesis if it occurs within a coding region, which can lead to significant changes in the resulting protein.

Deletions can alter the sequence of amino acids in a protein, potentially resulting in a nonfunctional or dysfunctional protein, depending on where in the gene the deletion occurs and how many nucleotides are removed. This contrasts with other types of mutations, such as substitutions, where one nucleotide is replaced by another, and duplications, where sections of DNA are replicated, adding extra nucleotides instead of removing them. Translocations involve the relocation of a segment of DNA from one chromosome to another and do not involve the direct loss of nucleotides from a segment.