DNA profiling was developed in 1985 by British geneticist Sir Alec J. Jeffreys. He first used it as forensic science to help convict Colin Pitchfork in a murder case. The term “DNA fingerprinting” was coined by Jeffreys at the University of Leicester, U.K.

Jeffreys’ method produces a complex pattern of bands from particular regions of the DNA molecule called minisatellites. Experts claim that the patterns are as unique to an individual as his or her fingerprints. Specific genetic fingerprints can be obtained from minute samples of blood, skin cells, semen, or even a single hair. The condition or age of these biological samples do not affect the ability of the method to produce DNA fingerprints. The specificity and flexibility of genetic fingerprinting make it an ideal tool for forensic investigations and criminal prosecutions.

Today, as a result of Jeffreys' work, DNA profiling techniques have specifically led to the exoneration of wrongly convicted felons all over the world.

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