DNA was discovered in the sperm of Rhine River trout in 1871. Today, technology is so advanced that a made-to-order piece of DNA can be bought at the University of Florida almost as easily as Xeroxing.

Identification of people by analyzing their DNA is one of the latest techniques to emerge from the profound discoveries of the past two decades. A short history:1970 The first restriction enzyme is discovered. Those enzymes, which cut DNA in specific places, would make possible large-scale decoding of genetic material.

1972 Paul Berg of Stanford University, who later won the Nobel Prize, creates the first recombinant DNA molecule by joining fragments cut with enzymes from two different viruses.

1978 Y.W. Kan of the University of California at San Francisco shows that differences among people can be identified by comparing the dark bands produced by their DNA when it is cut with restriction enzymes and put into an electrically charged gel.

1980 Research by Ray White at the University of Utah shows that even small parts of the long DNA chain are unique to individuals, meaning that there is enough variation to use the pieces to identify people.

1983 Research by James Gussela of Massachusetts General Hospital leads to discovery of a genetic marker located near the gene causing Huntington's disease, a fatal brain disorder.

That is a major step toward finding the causes of more than 3,000 inherited diseases and possibly treating them with gene therapy.

1985 British researcher Alec Jeffreys coins the term "DNA fingerprint" to describe his method of DNA identification. Other methods are also commercially available.

1987 The first conviction in a U.S. court using DNA evidence is obtained in an Orlando rape case.