DNA fingerprinting, also known as DNA typing, is the analysis of DNA (deoxyribonucleic acid) samples through isolation and separation. This identification technique is called “fingerprinting” because, like a real fingerprint, it is very unlikely that anyone else in the world will have the same pattern. Only a small sample of cells is needed to successfully perform a DNA fingerprint. For the DNA test, the root of a hair, a single drop of blood or a few skin cells are sufficient. DNA fingerprinting has many uses, some of which include crime scene investigations and paternity cases. A British geneticist, Sir Alec Jefferys, is credited with developing the technique of DNA fingerprinting on 10 September 1984. Alec Jefferys was attending the University of Leicester at the time of the murder. his development of this technique. Jefferys noticed the existence of certain sequences of DNA strands, or minisatellites, that do not aid the function of a gene but are duplicated within the gene. Jefferys also concluded that each organism has a unique pattern of these minisatellites and that the only exception was identical twins or multiple individuals from a single egg. The procedure to perform and create a DNA fingerprint is to obtain some cells with DNA in them, extract the DNA from them, and isolate and purify the DNA. Restriction enzymes then cut the DNA at certain points, leaving DNA fragments of different lengths. These DNA fragments are then selected through a process called gel electrophoresis. Gel electrophoresis is done by injecting DNA fragments into a gel, (agarose), and then passing an electric current through the gel causing the fragments to travel, the shorter the fragment, the further it travels. The gel is......in the center of the paper......determines whether a product is fresh or processed. This can be derived from the PCR test since PCR test results have a sensitivity and specificity close to 100%. Another application of PCR is in a crime scene investigation in New Jersey in 1994. The criminal's DNA was old and not as reliable or abundant as it should have been. The forensic scientist involved in the case used PCR to replicate his old, scarce DNA into fresh, abundant DNA that was later used to identify and imprison the criminal. Advances in biotechnology allow justice to be served to those who deserve it, but they can also help assist us in paternity cases or help prevent the spread of infectious diseases. Biotechnological advances improve the world at large, making it a healthier and safer place to live. DNA fingerprinting, combined with PCR, is nearly 100% accurate and has numerous applications.