Touch DNA is the new rage in DNA testing. It’s DNA obtained from fingerprints and from objects that have been touched. This contact deposits oils, debris, and skin cells on the surface touched. Cells that contain DNA. These cells can be collected, amplified through PCR (Polymerase Chain Reaction), and profiled by STR (Short Tandem Repeat) Analysis.
But what of a kiss? Same thing. Lips pressed to a cheek will also deposit skin cells.
Ask “Pierre G,” the as yet unnamed Parisienne jewel thief who gave his victim a peck on the cheek, apparently to “allay her trauma.” Very kind of him. Unfortunately for him, the police swabbed the woman’s cheek and found usable DNA from the thief. Some acts of “kindness” go unrewarded, I guess.