Which type of mutation results from the deletion of one or more nucleotides from a specific sequence?

A deletion mutation occurs when one or more nucleotides are removed from a DNA sequence. This type of mutation can have significant effects on the resulting protein, particularly if it takes place within a coding region of a gene. The deletion can shift the reading frame during the process of translation (called a frameshift mutation), resulting in a completely different sequence of amino acids downstream from the point of deletion. This can lead to nonfunctional proteins or truncated proteins if the deletion causes a premature stop codon.

By contrast, a substitution mutation involves altering a single nucleotide without changing the reading frame, while an insertion mutation adds one or more nucleotides to the sequence, which can also lead to frameshifts if not in multiples of three. A missense mutation specifically alters one amino acid in a protein sequence due to a single nucleotide change but does not necessarily involve the deletion of nucleotides.

Thus, the definition and consequences of a deletion make it distinct and illustrate why it is considered a specific type of mutation involving the loss of nucleotides.