DNA fingerprinting, also called DNA profiling, applies a test to determine the unique DNA sequence that each person has for the purpose of identification. In the 1930s, police detectives found each person has different patterns on the tips of the fingers, and these fingerprints became the standard for identification. However, the finger patterns can be altered by surgery or other means. DNA within living cells is difficult to alter.

Sir Alec Jeffreys at the University of Leicester invented genetic printing in the mid 1980s. The DNA profile is similar to a fingerprint, existing only for that person. Jeffreys coined the term DNA fingerprint and envisioned its powerful use. A single hair, a drop of blood, semen, or other body fluid can reveal the identity of a person. DNA fingerprinting is used for identifying people, studying populations...