To be successful, those searches required the DNA belong to someone previously convicted, or to a close relative who also was a felon and therefore in the database.In the East Area Rapist case, investigators have said they uploaded a genetic profile into an open source DNA database used by amateur genealogists searching for relatives, providing a much wider pool of potential matches.
"They were confident they would be able to get something off it," Poyser said.
He said the envelopes had been sent to the lab a few months ago, before Joseph De Angelo, who is suspected of being the East Area Rapist, was caught after investigators used a DNA profile run though an open-source database.
Arthur Leigh Allen, a former elementary school teacher and convicted child molester who lived in Vallejo, long was considered a top suspect.
Allen died in 1992 at the age of 58, according to media reports.
The Zodiac Killer roamed Northern California from December 1968 through October 1969, but was never caught despite at least one close run-in with police.