Long back story that involves some local vandalism done and several neighborhood kids that could be involved. The police said they were going to have DNA testing done on some feces that were left at the scene, but I didn’t think you could do that. There’s not a great deal of you in your poop is there? What’s the story here?
As our Perfect Master has told us, shit is brown because of the quantity of dead red blood cells it contains. Presumably DNA can be extracted from old blood.
Red blood cells have no nucleus and therefore no DNA. White blood cells (which are present in stool) OTOH, have nuclei. However, something like 80% of the dry weight of stool is bacteria which would contain their own DNA. I would be surprised but not shocked if there was a reliable method for DNA typings from stool.
Forensic DNA testing can indeed be done on fecal matter, using the handy dandy QIAamp DNA Stool Mini Kit.
Shouldn’t the surface of the stool be covered in epithelials from the mucus membrane in the rectum? If you can get a sufficient sample from swabbing the inside of a cheek, I’d have thought you can get one from swabbing the outside of a turd.
Sometimes it’s more important for the neighborhood kids to think they may be caught than to actually be able to catch them. I have to think that if word got back to the kids, they’d start to confess and rat out the ringleader(s).
Which is what I figured was the case, nobody is going to send out two month old poop for really expensive DNA testing to what apparently amounts to $1500 worth of damage. But after thinking about it it make me curious to know if it could even really be done. Although I would like to be in court the day that exhibit one, a bag of poop, is presented as evidence.
Huh. Colour me surprised but not shocked. 
A local politician in Vienna, Austria wanted a DNA database of all dogs in the city. The idea was any poop that’s not picked up could be matched to a particular dog.
DNA testing done on the dog poop that covered Tawana Brawley proved it belonged to a dog that lived in the apartment complex where she was found,
Cells form the colon mucosa are shed in the stool all the time and you can extract their DNA and use it. You don’t even need a lot of feces, just 200 mg.
Short answer, yeah, but it’s not fun.
Long answer: there’s some of your DNA in there, but there’s obviously a lot of other crap (heh) to get through. As has been mentioned, there are a lot of old dead red blood cells and bacteria, as well as fats and other miscellaneous proteins. So it can be done, but usually there’s an easier way to get what you want.
I can’t believe I forgot that.
–slinks away–