neutral mutation
"A neutral mutation is like a missense mutation except that the amino acid change does not affect the function of the protein. A silent mutation is like a neutral mutation except the codon change does not result in an amino acid change. Nonsense mutations replace a codon specifying an amino acid in protein with UAG, UGA, ..."
"We can also ignore the neutral mutations, for another reason: not because they are rare but because they are irrelevant. A neutral mutation is like a 'mistake' that does not alter the message. A neutral mistake could be something like a spelling variant, as if the speaker imagines the word as TYGER and the receiver imagines ..."
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