I don't know if this belongs here, but it's a fascinating use of DNA. An old crime was solved with the DNA of a 14 year old kid who wasn't even alive at the time of the crime:
http://www.msnbc.msn.com/id/12743184/
http://www.msnbc.msn.com/id/12743184/
British police ran the results through a national DNA database of known criminals, but didn't turn up anyone with an exact match. They did, however, notice someone whose DNA profile was close: a 14-year-old boy who was not even alive when White was murdered but who had gotten into trouble with the cops.
DNA testing of the boy's family eventually led police to Jeffrey Gafoor, the boy's paternal uncle, whose DNA exactly matched that of the blood sample. When questioned, Gafoor admitted to murdering White.
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Studies have shown that a person's chances of committing a crime go up if a parent or sibling had previously done so. And a 1999 U.S. Department of Justice survey found that 46 percent of jail inmates had at least one close relative who had been incarcerated.
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"On one hand, it's not right to put in a whole class of people who have never been convicted, arrested or suspected of a crime under lifelong genetic surveillance," Lazer told LiveScience. "But on the other, it would be morally repugnant not to catch a murderer if all it takes is a click of a button to activate the search algorithm."