A decades-old cold case has been solved after detectives were able to identify a body found in 1978 as that of a missing Iowa teenager. 

Police said the body of "Lincoln County Jane Doe" was found in 1978. The remains were found in the Mississippi River, near Elsberry, Missouri, the Lincoln County Sheriff's Office said in a news release. An autopsy determined that the body was that of a White woman, believed to be between 30 and 40 years old, who had died by drowning. It was determined that the remains had been in the river for about four months, the sheriff's office said. 

Only a few details could be determined about the remains. The body found was wearing a cat's eye ring and had a tattoo that appeared to say "Dee," police said, but attempts to identify the remains at the time failed. The remains were buried under a headstone that read "Lincoln County Jane Doe," police said. 

In 2009, details of the case were uploaded into the National Missing and Unidentified Persons System. 

It wasn't until 2023 that officials made a "pivotal breakthrough," police said. The buried remains were exhumed, and analyses by anthropology faculty and students from Southeast Missouri State University determined that the body was that of a teenager, not a middle-aged woman as initially estimated. The university participants sent samples from the remains to Othram, a private DNA laboratory, for DNA extraction. The company was able to use forensic-grade genome sequencing, which allows a DNA profile to be formed from just a small sample. 

The genome sequencing allowed Othram's genealogy team to "generate new leads" with a "comprehensive genealogical profile," police said. The Lincoln County Coroner's Office contacted an individual who said they had a close family member who matched the Jane Doe's description, who had disappeared in 1977. A familial reference sample was collected. 

Testing confirmed a match between the remains and the family member, allowing officials to identify "Lincoln County Jane Doe" as Helen Renee Groomes, a 15-year-old who was last seen in her hometown of Ottumwa, Iowa. 

Kevin Groomes told local NBC News affiliate KSDK that he was "overwhelmed with joy" that his sister's remains had been identified. The exhumed remains have since been cremated. 

He said that his sister's tattoo read "Del" and told KSDK that he had put it there. It was the name of her boyfriend at the time, he said. 

"We are profoundly grateful to the teams at SEMO, Othram, and the Lincoln County Coroner's Office for their invaluable contributions, which proved to be instrumental in finally solving this decades-old mystery and bringing closure to a grieving family," said Lincoln County Sheriff Rick Harrell.

An investigation into Groomes' disappearance and death is ongoing, the sheriff's office said. 

In:
• Iowa
• Missing Girl
• Missing Child

Kerry Breen

Kerry Breen is a reporter and news editor at CBSNews.com. A graduate of New York University's Arthur L. Carter School of Journalism, she previously worked at NBC News' TODAY Digital. She covers current events, breaking news and issues including substance use.

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