A mutation has occurred during DNA replication while the cell was preparing to divide. As a result of this, the codon ACU of mRNA has now become ACC. Interestingly, there is no change to the protein being made. Why not?

Question

Quizplus · Accepted Answer

This is an example of a silent mutation, where the change in the nucleotide sequence of the mRNA does not result in a change in the amino acid sequence of the protein. This is due to the redundancy in the genetic code, where multiple codons can code for the same amino acid. In this case, both ACU and ACC code for the amino acid threonine, not isoleucine or leucine as suggested in option B.

A Mutation Has Occurred During DNA Replication While the Cell