Which type of mutation results in the production of shorter and typically nonfunctional proteins?

A nonsense mutation leads to the production of shorter and often nonfunctional proteins because it introduces a premature stop codon into the coding sequence of a gene. Normally, the codons in the mRNA dictate the sequence of amino acids in a protein, but when a stop codon appears prematurely, translation of the mRNA is terminated earlier than intended. This results in a truncated protein that may lack essential functional regions, ultimately affecting its ability to perform its biological role effectively.

In contrast, a silent mutation does not change the amino acid sequence of the protein because it typically occurs in a coding region where it substitutes one codon for another that codes for the same amino acid. A missense mutation changes one amino acid in the protein sequence, which can lead to proteins that are functional but may have altered properties or efficiencies. Neither silent nor missense mutations create a premature stop codon, hence they do not generally produce shortened or nonfunctional proteins like a nonsense mutation does.