How it began
In 1984 Alec Jeffreys discovered the technique of genetic fingerprinting in a laboratory in the Department of Genetics at the University of Leicester. The United States National Library of Medicine records that in that year he and colleagues devised a way to use a newly discovered property of DNA for forensic identification, producing the original DNA fingerprint.
Before it existed
The University of Leicester's history of the field begins with the discovery of blood groups in 1900 and runs through a century of human genetics to Jeffreys's work. Before 1984 there was no method that used the variability of DNA itself to identify a person for forensic purposes.
How it works
The method relies on isolated areas of DNA that vary greatly between individuals, known as restriction fragment length polymorphisms. The University of Leicester describes the technique as resting on short sequences within DNA. Because the pattern of these variable regions differs from person to person, it can be used to tell individuals apart, in the way a fingerprint does.
What lasted
The National Library of Medicine treats Jeffreys's method, and its use in the Pitchfork murder case, as the origin of DNA profiling in criminal investigation. Jeffreys continued research and teaching at Leicester, including work on the genetic legacy of Chernobyl, and retired in 2012 after more than 35 years at the university.
