It's exciting to think that we can test for DNA left on artifacts after 70 years. But, wouldn't all artifacts have the DNA of everyone that ever touched it from manufacture to distributor to consumer (AE)?
In theory, yes, but from a practical standpoint there should be far more DNA from a recent and intensive handler. For example, the zipper pull on your fly might have some trace of DNA form someone at the factory that made it but chances are any retrievable DNA is your own .... unless ..... probably best not to go there.
Ric