When a substitution mutation changes the codon ccc to the codon cca, both code for proline. what type of mutation is this?

A substitution mutation changes the codon CCC to the codon CCA, both code for proline, the type of mutation happens in this case is called as "Silent mutation"

Explanation:

It is a base substitution method without a change in the  amino acid. In some cases.In this method of mutation ,the amino acid is changed while the translation of mRNA. Example, when CCC is altered to form CCA, the amino acid remains same, as well as both the code for the proline. Silent mutation happens due to the result of change in the single DNA nucleotide, inside the protein coding. This alteration or change will not affect the sequence of amino acid rather build up the gene's protein. They never show any effect on the growth and survival of the living being.

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