A mutation in which a sense codon that corresponds to one of the twenty amino acids specified by the genetic code is changed to a chain-terminating codon.
- ‘A nonsense mutation is represented by a solid red circle.’
- ‘The first spans codons 195-196 and induces a silent substitution at codon 195 and a nonsense mutation at codon 196.’
- ‘The proximity of the nonsense mutation to the start codon indicates that these mutations are null alleles.’
- ‘Another mutant isolated from the screen, LPY727, contained a nonsense mutation at amino acid 15.’
- ‘Another nonsense mutation at codon 187 is shared by the human, the chimpanzee and the gorilla, so that it is most likely to have occurred in their ancestral species.’