Very few people understand the science behind dog poop DNA and why companies like Mr Dog Pop are able to match a dog's poop with the dog.
The way it works is by isolating genetic markers that are unique to dogs, short sequences of about 20 nucleotides that can be compared from one sample to the next.
Since dog poop comes out of a dog, it naturally has some of the dogs DNA just like saliva, blood, hair or anything else on the dog.
We isolate just the markers that we know can only come from a dog, not human, not a cat or anything else with DNA. That way, there will not be any cross contamination when a human collects a sample.
We then test saliva samples from each dog and compare those samples with the dog poop samples using capillary electrophoresis to measure the sizes of each genetic marker,
The sizes are compared to find matches.
The sizes of each dogs markers are different and have been inherited from their parents, so no two dogs will have the same sizes of markers.
While some markers will be the same size, over the spectrum of 24 markers used there is virtually no possibility that any 2 dogs will match.
Think of it like a lottery ticket. You might match 1 or 2 of the numbers, but without all 5 or six you are not a winner. In that base there are tens of millions of possible combinations which is essentially how the dog markers work.
A series of markers with some set possible values inherited from the mother and father will create a numeric sequence that can be matched only by the winner, the dog that pooped the poop.
While the science in analyzing the dog poop is quite extensive, the theory is very simple and well documented over many years of research.
The FBI uses genotyping to match human offenders but so far the federal government has not made dog poop a top priority despite so many people wishing that they would.
Obviously the markers for humans and dogs are quite different but the science is exactly the same.
So those dogs can be matched to their poop just like humans can be matched to their DNA left at crime scenes.
So if you are leaving that dog poop out in the open, don't be surprised if someone is picking it up and sending it out for DNA analysis.