Question

A scientist creates fruit fly larvae with a mutation that eliminates the exonuclease function of DNA pol III. Which prediction about the mutational load in the adult fruit flies is most likely to be correct?

The adults with the DNA pol III mutation will have significantly more mutations than average.

The adults with the DNA pol III mutation will have slightly more mutations than average.

The adults with the DNA pol III mutation will have fewer mutations than average.

The adults with the DNA pol III mutation will have the same number of mutations as average.

Answer 1

Answer: Option A is correct
Explanation:
DNA pol III exonuclease activity is required for proof-reading function.
i.e. It detects mismatches during replication and removes the entire strand till the lesion.
If 3'-5' exonuclease activity is lost, there would significantly more number of mutations than average.