Silent mutation

Point substitution mutations of a codon, classified by their impact on protein sequence

Silent mutations are mutations in DNA that do not have an observable effect on the organism's phenotype. They are a specific type of neutral mutation. The phrase silent mutation is often used interchangeably with the phrase synonymous mutation; however, synonymous mutations are not always silent, nor vice versa.[1][2][3][4][5] Synonymous mutations can affect transcription, splicing, mRNA transport, and translation, any of which could alter phenotype, rendering the synonymous mutation non-silent.[3] The substrate specificity of the tRNA to the rare codon can affect the timing of translation, and in turn the co-translational folding of the protein.[1] This is reflected in the codon usage bias that is observed in many species. Mutations that cause the altered codon to produce an amino acid with similar functionality (e.g. a mutation producing leucine instead of isoleucine) are often classified as silent; if the properties of the amino acid are conserved, this mutation does not usually significantly affect protein function.[6]

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  3. ^ a b Goymer P (February 2007). "Synonymous mutations break their silence". Nature Reviews Genetics. 8 (2): 92. doi:10.1038/nrg2056. S2CID 29882152.
  4. ^ Zhou T, Ko EA, Gu W, Lim I, Bang H, Ko JH (31 October 2012). "Non-silent story on synonymous sites in voltage-gated ion channel genes". PLOS ONE. 7 (10): e48541. Bibcode:2012PLoSO...748541Z. doi:10.1371/journal.pone.0048541. PMC 3485311. PMID 23119053.
  5. ^ Graur D (2003). "Single Base Mutation" (PDF). In Cooper DN (ed.). Nature Encyclopedia of the Human Genome. MacMillan. ISBN 978-0333803868.
  6. ^ Alberts B, Johnson A, Lewis J, Raff M, Roberts K, Walter P (2007). Molecular Biology of the Cell. Garland Science. p. 264. ISBN 978-1-136-84442-3.