The Neighborhood's DNA

I've noticed DNA spray notices springing up around Amsterdam.  I assumed it was a fairly standard anti-theft device:  A crime is committed, a little nozzle is activated by the offended shop owner, and the criminal is coated in a long-lasting UV-dye.  So far, a more advanced update of the standard 'exploding ink in a wad of money' trick, but nothing unusual.   The DNA angle seemed like a marketing ploy to make a banal technology sound bio-futuristic.

It turns out that the dye actually does contain synthetic DNA unique to each location.  The company is a bit cagey is to the exact composition of their 'DNA solution,' assuring customers only that it contains all relevant information and is 100% non-toxic.  The genome may be synthetic, but if it is composed of a double-helix polymer made of nucleotides, then it is certainly not fake.

Here, the DNA does not code for a living organism.  It codes for an event (the crime), and it codes for a location.  We often talk of neighborhoods having a personality, or of cities having a character.  DNA spray pushes the urban environment one step towards actual personhood.  Particularly enterprising thieves will mix the genetic material, bumblebee-like, and encode for as-yet-built locations.  Future crime-prevention tech may create bespoke infections that produce flamboyant symptoms, or custom parasites that make crooks fond of truth-telling and police stations.