Calif. Mom, 24, Was Raped and Strangled in 1969, and a Man Was Just Arrested Using Preserved DNA

Handout Mary Scott

More than 50 years after she was raped and killed, a suspect has been identified in the slaying of a San Diego go-go dancer and single mom of two — thanks to the preservation of DNA evidence in the case, and recent advancements in DNA science.

On Nov. 20, 1969, Mary Scott, who co-workers nicknamed "Lucky," was found strangled to death in her ground-floor apartment in San Diego's City Heights neighborhood.

This past weekend, authorities in Pennsylvania took 75-year-old John Sipos into custody for the 51-year-old crime.

Investigators reopened the case last year at the urging of Scott's sister.

Long-preserved DNA evidence collected at the scene was run through forensic genealogy databases, returning a match on Sipos, who was arrested on suspicion of murder.

Sipos' arrest — at his residence in Schnecksville — was announced Tuesday, and he is awaiting extradition to the west coast.

"It is unbelievable," said Rosalie Sanz, Mary's younger sister, speaking to KFMB-TV. "She had a whole life ahead of her. Who knows what she would have done, what she would have become, what dreams she could have pursued? We don't know. We'll never know."

Mary, a single mom of two daughters who went to live with her husband's family after the couple separated, worked at Star and Garter, a go-go club blocks from her apartment. When she failed to show up for work on Nov. 20, 1969, a friend went to her apartment looking for her.

The friend arrived to find the door kicked in and Mary's nude body on the floor. Mary had been brutally raped before being strangled to death.

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"She only saw good in people," Sanz told the station.

At the time of the killing, Sipos was based in San Diego, where he was serving in the U.S. Navy. Police have not said if he was ever a suspect in the killing, and have yet to establish how the alleged killer may have been connected to the victim.

Sipos, who has yet to enter a plea, is being held on $3 million bail.

Attempts to reach his attorney were unsuccessful Thursday.