How could a dna paternity test go wrong?

Question

How could a dna paternity test go wrong?

Answer 1

generally they don't, but you can check the chain of custody that was followed. They should have a copy of ID, photo, and fingerprint of the parties tested.

Answer 2

A friend of mine once tried to tell me that if the guy puts someone else's spit in his mouth right before they take it that it would affect the results. I don't think it's true though because as far as I know they scrape the inside of the cheek.. They could mix results up at the lab.

Answer 3

it doesn't ! It is 99.99% accurate and that is that.. We need more info on your situation to give you a better answer