DNA testing is different than Body fluid testing. I am a Forensic Serologist, I do both. You can test for saliva, yes. And you can test for DNA. DNA comes from nucleated cells, of which there are alot in saliva. So if you get alot of DNA from a sample that is positive for amylase type I (Salivary), you can say it is reasonable it came from the saliva. But you can't tell for sure what type of cell the DNA came from other than the fact that it was nucleated, like a white blood cell, nucleated epithelial cell or spermatozoa cell.....
