Why bother when it's trivial to copy existing DNA? The evildoer just needs to get a tiny sample from someone who'd made a decent frame.
Sure, then you've got the problem of how to create a DNA-bearing artifact that'll fool forensics -- a spilled puddle of pure chromosomes would be weird -- but that'd be true in either case.
0: https://www.chicagotribune.com/news/ct-xpm-1998-05-05-980505...
They may be able to pinpoint a location - the barber where all the DNA matches go to have a haircut, and a time - soon after all those with majority DNA in the pile of hair went to the Barber's. Then they can analyse who was in the area around the time and find a person involved.
Can you point to current DNA tech which doesn't destroy the sample while processing it?
https://www.nytimes.com/2019/09/16/science/hair-dna-murder.h...
Go to two or three libraries in different corners of town, get what you want from the keyboards, and you should have quite the collection of DNA.
The word for this type of accumulation of mixed biological material, crumbs, dandruff, eyelashes, and such is "kroonch".
It's like snatching handbags vs online credit card fraud - the reach of criminals to victims got a lot bigger.
$150 for 10 groups: Edvotek 330 Amplification of DNA by PCR, For 10 Lab Groups https://www.amazon.com/dp/B004W7ZAYI
Bad part about that - even today - is that we know for a fact that what people remember/recall isn't necessarily what actually occurred. Also, as time goes on, those recollections can become more unreliable.
We know that the mind confabulates, making things up to fill in gaps - both at the time something occurs, and after the fact to "fill in the story".
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4183265/
https://faculty.sites.uci.edu/starklab/false-memory-eyewitne...
Unfortunately, the legal system has been slow in acknowledging this - on top of so many other things found and/or known to be false or bias - two big ones are so-called "lie detector" systems, and "blood spatter analysis".
Fortunately, lie detector "evidence" is generally not admissible in the United States (at least I think for criminal cases?) - but blood spatter analysis is still considered to be a "real science", when it may be anything but:
https://features.propublica.org/blood-spatter/blood-spatter-...
We had this brief period of history where good records of actual events were cheap to capture and expensive/impossible to fake (governments have been airbrushing photos for most of this period, but videos seem to have been tougher). We're at the end of that now, but the public hasn't quite caught on. I think it'll take at least one high profile case getting overturned before society at large stops believing in videos. Then we're essentially back to trusting people at their word/digital-signature, and we'll probably have "trusted" security camera companies that install tamper-proof cameras at multiple angles that cryptographically sign videos while streaming them to remote servers. Before that, and probably after it as well, some of us will rot behind bars based on state-forged evidence.
A partial or even complete match is not enough to convict anyone.
From what I know about CRISPR, and forensic DNA testing, it should be extremely difficult or impossible to, for example, change your "genetic fingerprint" as it is called.
If I remember correctly, those methods primarily use repetitive patterns, which should be hard to modify with CRISPR. And you'd need to modify hundreds of them, and in billions of cells of your body (even if you try to only get white blood cells and their progenitors).
The real nightmare is that we might be right around the corner from DNA being writable to the extent that you could make mock DNA to plant at a crime-scene/evidence-locker, and there might be a couple awkward decades where the courts believe the FBI when they claim to have found DNA matches (just like that time they systematically pretended they could identify hairs, and convicted people of murder based on hairs that were literally from dogs in some cases). We'll catch on eventually if they try it, but it would suck for those of us convicted on falsified evidence. I wouldn't be so paranoid about that possibility if they hadn't lied about the dog hairs for decades.