Question

The original base sequence of DNA is : CAG TTA CCA. If the amino acid sequence that results from translation of this DNA base sequence is: valine-tyrosine-glycine, what mutation occurred in the DNA? Explain

A. An addition mutation occurred
B. A deletion mutation occurred
C. A substitution mutation occurred
D. A mutation did not occur.

Answer 1

C

I think substitution, because the original translation of the original base sequence is glutamine-leucine-proline. The base sequence for valine-tyrosine-glycine is: GT# TA# GG# . of course the last codon is unclear, but the first two gives us enough to know too much change happened for a simple addition or deletion mutation. The bases were completely switched out, therefore it is a substitution mutation. I attached a codon chart.