DNA / Serology

Serology is the study of body fluids: blood, saliva, semen, and urine.

From biological evidence left at a crime scene, such as hair or semen, DNA analysis (or DNA typing) can be used to identify an individual. The most widely used methods of DNA typing are Restriction Fragment Length Polymorphism (RFLP) and Polymerase Chain Reaction (PCR).

The RFLP process is a long, labor intensive procedure that involves extracting DNA from the biological sample, fragmenting the DNA with special (restriction) enzymes and separating the molecular pieces by gel electrophoresis.

PCR is a technique by which a miniscule and/or degraded amount of DNA can be quickly amplified. This is beneficial in cases where only small quantities of evidence are discovered.