the dna fragments must then be sorted out but a process called electrophoresis. it s marked with an radioactive dye and placed in separate lanes with a gel. then it s subjected to an electric field. under ultraviolet light you can see how the electrical current draws the negatively charged fragments through the gel to the positive end of the tray. the separated fragments are then visualized on x-ray film which resembles a bar code showing an individual s unique genetic makeup. dr. jeffries first used this technique to resolve an immigration case and after that a paternity dispute. but this would be first time it was ever attempted in a criminal case to reveal the identity of a double murderer. let s start with lynda mann. that is her dna profile from her hair. the next is a mix of semen and vaginal fluid from the victim, plus a single man semen dna