Alec John Jeffreys (1950) is an English geneticist, who developed techniques for DNA fingerprinting and DNA profiling which are now used all over the world in forensic science to assist police detective work and also to resolve paternity and immigration disputes. DNA profiling based on typing individual highly variable mini-satellites (section of DNA that consists of a short series of bases 10-60 bp in the human genome) was also developed by Alec Jeffreys and his team in 1985, with the term DNA fingerprinting being retained for the initial test that types many mini-satellites simultaneously. By focussing on just a few of these highly variable mini-satellites, DNA profiling made the system more sensitive, more reproducible, and amenable to computer databasing.