1. José Gerardo Cruz Rivera804-10-1716<br />Forensic DNA Fingerprinting<br />DNA was invented by Alec Jeffreys at the University of Leicester in 1985. DNA fingerprinting (genetic fingerprinting or DNA profiling) is a way of identifying a specific individual, rather than simply identifying a species or some particular trait. DNA fingerprinting can be used for identifying paternity or maternity and for identifying criminals or victims. DNA fingerprinting uses a specific type of DNA sequence, known as a microsatellite, to make identification much easier. Microsatellites are short pieces of DNA which repeat many times in a given person's DNA. The steps to follow in order to make DNA fingerprinting are: isolation of DNA, cutting, sizing, and sorting. You can isolate DNA from blood, hair, saliva, or semen. You use an enzyme to cut DNA. These DNA pieces are passed through a gel made from seaweed agarose. The Polymerase Chain Reaction (PCR) helps to amplify the small amount of DNA by heating and cooling it. These DNA fragments are injected into wells and an electric current is applied along with the gel. Since the DNA is negatively charged, it is attracted to the positive end of the gel. Finally, the segments are analyzed to discover who was the guilty of the crime, and in this case it was suspect number three, because his DNA had the same segment as the DNA segment found at the crime scene. <br />