The Polymerase Chain Reaction, or PCR, is used to prepare large quantities of specific DNA regions from small samples recovered from crime scenes. The laboratory utilizes automated genetic analyzers that subject the DNA to capillary electrophoresis to determine DNA profiles.
The laboratory participates in the FBI Combined DNA Index System, or CODIS, a network of local, state and national DNA databases. CODIS links DNA profiles of evidence from unsolved crimes to DNA profiles from convicted offenders and from DNA profiles of other crimes.
The Harris County Institute of Forensic Sciences has developed a DNA Collection Guide to assist officers in obtaining the best possible DNA samples from crime scenes. The guide provides step-by-step instructions for collecting, labeling and packaging of DNA samples and includes a list of the supplies needed to ensure success.