Do you know the definition of the word "duplication?" It does not add anything to DNA.
As far as mutation goes, what form of mutation that we have observed (outside of movies) is beneficial?
You do know that scientists have been studying for decades, looking for ways to treat diseases, etc.?
In the last week, an gene "edit" was performed medically to treat a patient.
The uses of DNA appear to be well advanced, beyond your present knowledge.
The science of DNA is so well "settled," as to be used in evidence to convict and exonerate suspects in capital crimes, and to establish paternity.
DNA is very solid science. But some still cling to Rev. Benny Hinn, for his "science."