- A nonsense mutation changes a codon that codes for an amino acid into a premature stop codon, leading to early termination of protein synthesis.
- This results in a truncated, often nonfunctional protein. In contrast, missense mutations substitute one amino acid for another, silent mutations do not change the amino acid, and frameshift mutations alter the reading frame, potentially causing many downstream changes but not specifically introducing a premature stop codon.

Reference: Molecular Biology of the Cell, 6th Edition, Chapter 4, Page 150