no , i meant its not hard to do. lol i wasnt trying to be a dick.
its an easy way to distinguish between DNA. you take several enzymes called endonucleases which cut DNA at specific sequences. cut up someones DNA with it, and run a Gel on it and see where the bands fall. different people have different lengths each band will travel. when you look at 14 places in a region of DNA that is already ''hypervariable'' (a couple different locations are commonly used) and you see where the DNA was cut at, there are astronomically low odds of having the same DNA if youre not the culprit.
think about it like this. if you have an something which cuts DNA at this sequence
CAATAAC
Could this possibly be 2Thick? If it is, you sure fooled the hell out of me? Come on man. He didn't like cats and he never joked around that much.
everyone will have that sequence somewhere.
say you have that sequence in a place that is 20k bases long. well someone with that same sequence that instead of in that place has CAGGAAC the enzyme will not recognize it and it wont cut there, so the piece of DNA will be longer between cuts at the sequence we know it will cut at. On a gel electrophoresis that translates to a marked difference in distance the band will move, so if its not the same person, they wont have the same banding pattern on a gel.