nonsense mutation

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sup·pres·sor mu·ta·tion

1. a second mutation that alters the anticodon in a tRNA so that it can recognize a nonsense (stop) codon, thus suppressing termination of the amino acid chain. Compare: amber mutation, ochre mutation, umber mutation.
2. genetic changes such that the effect of a m. in one place can be masked by a second m. in another location. There are two types: intergenic suppression (occurring in a different gene) and intragenic suppression (occurring in the same gene but at a different site).
Synonym(s): nonsense mutation

nonsense mutation

A POINT MUTATION which changes a CODON that specifies an amino acid into a termination codon-one that marks the position where translation of a messenger RNA sequence should stop. The result is a gene with a segment lopped off. Such a gene will code for a protein that may have missing amino acids and may thus be functionally defective.

nonsense mutation

an alteration in a DNA POLYNUCLEOTIDE CHAIN that results in a NONSENSE CODON when transcribed on to mRNA.
References in periodicals archive ?
Nonsense mutation in the glycoprotein Ib alpha coding sequence associated with Bernard-Soulier syndrome.
A nonsense mutation of the human luteinizing hormone receptor gene in Leydig cell hypoplasia.
A class of small molecule drugs, in particular one named ataluren (also known as Translarna), can bind to the protein-making machinery within the cell (the ribosome) and weaken its ability to detect abnormal stop signals resulting from nonsense mutations. The ribosome is involved in translation of a protein by reading the transcribed instruction part of the gene (also known as the messenger RNA, mRNA or transcript) and detecting the sequence of three letter codes (codon) to join amino acids together to form a protein.
Caption: Figure 4 - Sequence chromatogram showing a bialleic nonsense mutation changing adenine to thiamine at coding position 1412 (c.A1412T) leading to change of the amino acid Leucine to a stop codon with truncation of the protein at amino acid 471 (p.471 L>X).
A variety of RUNX1 mutations have been described, including frameshift or nonsense mutations or deletion throughout the gene as well as missense point mutations clustering within the highly conserved RUNT homology domain (RHD) and transactivation domain (TAD).
Identification of a nonsense mutation in the PAX9 gene in molar oligodontia.
Here, we report a previously reported homozygous nonsense mutation c.4802C>G in the ASPM gene (rs199422189) in two Pakistani families and provide clinical signs of patients with an ASPM mutation.
has received an award valued at up to USD 11m from the Bethesda, Maryland-based Cystic Fibrosis (CF) Foundation in support of its research on the discovery of therapeutics to treat patients with cystic fibrosis caused by nonsense mutations, the company said.
By changing an A to an I within a codon, its "readout" (translation to amino acid) within the ribosome can be altered, leading to missense mutations (substitution of one amino acid for another), nonsense mutations (substitution of an amino acid for a STOP codon), or STOP suppressions (substitution of a STOP condon for a sense codon, leading to a product with some random C terminal tail).
While missense mutations are frequently detected in VHL Type 2, missense and nonsense mutations are more frequent in VHL Type 1 (9) (Table II).
Among known MEN1 mutations, 41% are frameshift insertions and deletions, 23% are nonsense mutations, 20% are missense mutations, 9% are splice site defects, and 1% are whole or partial gene gross deletions [13].
The majority of mutations identified to date have been found to affect the Proline-glutamic acid-serine-threonine-rich (PEST) domain at the C-terminus of the receptor via frameshift or nonsense mutations [12].