What characterizes a missense mutation in DNA?

A missense mutation is characterized by a change in the DNA sequence that results in the substitution of one amino acid for another in the resulting protein. This occurs due to a single nucleotide change, or base pair alteration, that leads to codon that specifies a different amino acid during translation. The alteration in the amino acid sequence can potentially affect the structure and function of the protein, leading to variations in its activity or stability.

For example, if the original DNA sequence encodes for a codon that translates to glycine and a mutation changes that codon to one that codes for serine, the resulting protein will have a different amino acid at that position. This change can have significant biological consequences, depending on the role of that amino acid in the protein’s function.

The other options refer to different types of mutations or conditions that are not indicative of a missense mutation. The stability of the protein offered by missense mutations can lead to varying outcomes, depending on the specific amino acid change and its context within the protein structure.