The case of an unsolved slaying of a woman near Lake Tahoe that haunted detectives for more than three decades is closed after forensic genealogists used DNA to identify the victim and the man they believe killed her.

The suspect, authorities say, is a long-dead, self-proclaimed serial killer who confessed to killings in the Bay Area.

The Washoe County sheriff's office, which oversees the northern Nevada region where the woman’s body was found near a popular Lake Tahoe hiking trail in July 1982, said this week that DNA pinpointed James Richard Curry as the suspect who shot her.

The woman, named for the first time this week by police as Mary Edith Silvani, was found on the hiking trail in the Sheep’s Flat area near Mt. Rose Highway, just a few miles above Incline Village. Detectives at the time noted how she appeared to be dressed to spend a day at Lake Tahoe, wearing a bathing suit under a powder blue t-shirt, blue jeans and yellow tennis shoes.

Having found no identification card, authorities gave her the moniker “Sheep’s Flat Jane Doe.” It would be roughly 36 years later, during the summer of 2018, that police were finally able to identify the Pontiac, Mich., woman as Silvani, with the help of advanced DNA analysis through GEDMatch, the same DNA database used to identity the Golden State Killer.

Curry, who was born in Texas in 1946, was jailed in San Jose in January 1983 — just two days after he claimed to have shot a San Jose couple to death, roughly five months after Silvani’s killing, and nearly a year after he said he killed a Bakersfield man, police said.

He confessed to killing Gerald Novoselatz, 39, at the man’s home at 1020 Spring St. in San Jose on January 2, 1983. The body of Novoselatz’s wife, Sharon, 34, was found later that day on the side of Highway 92 in San Mateo County, said Sgt. Enrique Garcia of the San Jose Police Department.

Curry was arrested and taken to the San Jose Police Department on January 4, 1983, where he confessed to killing the couple. He also admitted to killing Richard Lemmon less than a year prior in February 1982, and stashing his body in a storage locker at a facility he managed at 1700 De La Cruz Blvd. in Santa Clara. Police later uncovered the body in the locker.

A day after he was arrested, Curry hanged himself in Santa Clara County Jail, Garcia said. He was placed on life support for two days and died on January 7, 1983.

Washoe authorities said he likely killed a coworker at a locksmith company in Waukena (Tulare County), but authorities said that victim’s remains have not been found.

“This is an incredible story and I am extremely proud of the work done by everyone who took part in this case over the past three decades,” Washoe County Sheriff Darin Balaam said Tuesday. “Even taking advantage of new genealogical technologies, a great deal of investigative work was done by Sheriff’s Office staff working this case.”

The positive identification of Silvani came after detectives failed to match her DNA, fingerprints and dental records to reports of hundreds of missing persons that matched her physical attributes. She had an “inoculation scar and unique dental work,” but she was not identified and her case remained unsolved for years, officials said.

In 2015, Dave Jenkins, a detective with a sheriff’s cold case unit, theorized that the victim may not have been reported as a missing person because she may have “voluntarily estranged” herself from her family and friends in the years leading up to her slaying.

“Detective Jenkins hoped that, based on this new theory, someone may have known of a young woman who left her family in the late 1970s, early 1980s and who has not been heard from since,” sheriff’s officials said in a statement. “Still, Sheep’s Flat Jane Doe’s identity remained a mystery.”

With the help of the nonprofit genealogy organization DNA Doe Project, sheriff’s detectives handed over samples of Silvani’s DNA to a private DNA lab in April 2018. The data was processed and uploaded to GEDMatch, where analysts searched for relatives sharing Silvani’s DNA.

Analysis of the DNA concluded Silvani was the biological daughter of a Detroit couple, John and Blanche Silvani. Investigators confirmed Silvani’s identification by matching fingerprints taken during her arrest on an unknown misdemeanor charge in Detroit in 1974.

Despite positively identifying Silvani in summer 2018 as the victim in the decades-old murder, officials said they withheld her name until they could find her killer.

Identifying the suspect proved to be a more difficult feat for investigators.

DNA evidence collected at the crime scene didn’t match anyone in the Federal Bureau of Investigation’s DNA database, Combined DNA Index System, known as CODIS. In 2018, the DNA evidence was sent to a private lab, where it was later uploaded to GEDMatch.

Dr. Colleen Fitzpatrick, a genealogist with the DNA Doe Project and IdentiFinders International, conducted more than 2,000 hours of research with a team of colleagues in an effort to track down relatives of the killer, sheriff’s officials said.

They determined the killer was the grandson of a couple who lived in Dallas. Further investigation led officials to Curry’s two children, who voluntarily provided DNA samples to a detective with the sheriff’s office. An analysis found the DNA collected at the crime scene was consistent with Curry’s children.

“Case closed,” sheriff’s officials said.

Fitzpatrick said in a statement that the thousands of hours of genealogical research was “only part of the story” of the case’s successful conclusion.

“With so few family members still alive, and with the fragmentation of the Silvani family, our hard-won success story would never have been possible without the investigative efforts of the Washoe County Sheriff’s Office,” Fitzpatrick said.

Sheriff Balaam said officials with the San Jose and Santa Clara police departments, and the San Mateo and Santa Clara county sheriff’s offices, also contributed to the case by providing historical information on their respective murder investigations.

Lauren Hernández is a San Francisco Chronicle staff writer. Email: lauren.hernandez@sfchronicle.com Twitter: @LaurenPorFavor