Nancy Guthrie case: FBI uses genetic genealogy technology on DNA evidence

Investigators are looking for a trace Nancy GuthrieSuspected kidnappers are turning to a relatively new technique credited with solving some of the most notorious criminal and cold cases in American history.

Investigative Genetic Genealogy (IGG) is defined as “the science of using genetic and genealogical methods to generate leads for law enforcement agencies investigating crimes and identifying human remains.” according to International Society of Genetic Genealogy.

Investigators use a DNA sample to search for genetic family matches, and ultimately look to narrow down potential identities by focusing on an individual’s close relatives.

Tuesday, Federal Bureau of Investigation Fox News Digital confirmed that IGG was used to test DNA found on a black glove discovered two miles from Nancy Guthrie’s home and other DNA samples found inside her home.

Harvey Levin gives explosive update on Nancy Levin Ransom’s alleged ‘Hannity’ memo

Savannah Guthrie and her mother Nancy Guthrie were photographed together in 2023. (Nathan Congleton/NBC via Getty Images)

The move comes after the two samples found no match in the nationwide law enforcement database, CODIS – which only includes individuals previously known to authorities.

This technology has been used to solve several high-profile cases in recent years, with the FBI now turning to IGG in hopes of identifying DNA found on a glove discovered two miles from Nancy Guthrie’s home and other samples found inside the home.

Here’s a look at previous cases in which IGG helped authorities locate a suspect.

Former FBI behavioral analyst says Guthrie is suspected amateur criminal, latest letter from Savannah tailored to him

This photo released by the FBI shows an armed person who appears to have tampered with the camera at Nancy Guthrie’s front door on the morning of her disappearance in Tucson, Arizona, Sunday, February 1, 2026. (Provided by the FBI)

Idaho homicides

Immediately following the brutal murders of four University of Idaho college students on November 13, 2022, investigators scrambled to track down the person responsible for killing Madison Mugen, Ethan Chapin, Zana Kernodle, and Kaylee Goncalves.

Using DNA found on the sheath of a Ka-Bar knife he left at the crime scene, authorities sent samples to Othram’s forensic lab after he returned empty-handed when CODIS was used.

An Idaho killer left behind “catastrophic” evidence that led to his quick arrest, investigators revealed

Brian Kohberger appears in Ada County District Court for a sentencing hearing, Wednesday, July 23, 2025, in Boise, Idaho, accused of brutally stabbing four University of Idaho students to death. (AP Photo/Kyle Green, Paul)

Outram was then able to create a DNA profile that matched the elements taken from him Brian Kohberger’s family trash in their Pennsylvania home, leading investigators to “a male who is not being ruled out as the biological father of the suspect file,” according to the affidavit.

Kohberger was then taken into custody on December 30, 2022, and pleaded guilty to the quadruple murders last summer as part of a plea deal to escape a potential death sentence.

He is serving four consecutive life sentences, plus an additional 10 years.

Detectives in the Nancy Guthrie case found a set of black gloves near the side of the road

Golden State Killer

More than three decades after 13 people were murdered and dozens raped, IGG finally led investigators to track down one of the world’s most prolific killers. In California history.

Using DNA collected from the crime scenes, authorities were able to match the profile created for the Golden State Killer to online genetic profiles. The findings pointed investigators toward a relative of former police officer Joseph James DeAngelo, who was arrested in 2018 and later charged with dozens of crimes.

Nancy Guthrie case: 5 key pieces of evidence so far

Joseph James DeAngelo, right, and Public Defender Joseph Kreis speak together during the first day of victim impact statements at the Gordon D. Schaper Sacramento District Court on Tuesday, August 18, 2020, in Sacramento, California.

“We were confident he was born between 1940 and 1960,” Paul Holz, a former investigator with the Contra Costa County Sheriff’s Office, told Fox News during a 2021 interview for a Fox Nation documentary and Fox News audio podcast “Grim Tide: Hunting the Long Island Serial Killer.”

“The common ancestors we used were great-great-grandparents,” Holz said. “These are people born in the 1840s, and we built a family tree of thousands.” “Eventually, we got to a branch in California with a small number of… males of the right age. And then, at that point, it was just ‘Investigation 101’. Who were these guys and could any of them be someone we need to look at more closely to be the person in charge?”

Prosecutors had previously called DeAngelo’s decades-long crimes “simply astonishing,” involving 87 victims at 53 separate crime scenes spanning 11 California counties.

The Nancy Guthrie case: All the possessions authorities have searched for since her disappearance

DiAngelo plead guilty to 13 murders and 13 rapes in 2020, and was later sentenced to life in prison without the possibility of parole.

Bear Brook Murders

Nearly 25 years after a dead body An unidentified little girl Discovered in a 55-gallon drum drum near Bear Brook State Park in New Hampshire, investigators used genetic genealogy to crack the final name listed on the infamous Allenstown Four.

Police have identified three bodies found inside barrels in a New Hampshire state park nearly two decades later

Genetic genealogy technology has revealed that Terry Rasmussen is the father of an unidentified girl who was found stuffed inside a barrel near Bear Brook State Park in New Hampshire in 2000. The girl was later identified as Rhea Rasmussen. (New Hampshire Attorney General’s Office; NCMEC)

From 1985 to 2000, authorities found four bodies stuffed into barrels in what were later ruled to be murders, and three of the individuals were identified as Marlyse Elizabeth Honeychurch, 24, and her two daughters, Mary Elizabeth Vaughn, 6, and Sarah Lynn McWaters, 1.

However, the identity of the final victim remained unknown until 2025, when authorities used genetic genealogy to determine that the little girl was Rhea Rasmussen. according to National Center for Missing and Endangered Children.

The four victims are believed to have been murdered by serial killer Terje Peder Rasmussen, Rhea’s biological father, who is suspected of killing six women and at least two children before his death in 2010.

Follow the FOX TRUE CRIME team on X

The case came to light in 2024, when New Hampshire State Police teamed up with the DNA Doe Project and learned that the mother of the unidentified child was a woman named Pepper Reed.

Reed’s family reportedly told investigators she was last seen Texas during Christmas In 1975, she later moved to California during her pregnancy. Her family identified Terry Rasmussen as the child’s father, which was later confirmed by a birth record located in Orange County, California.

Sign up for our True Crime Newsletter

Using DNA samples from Reid’s only surviving sibling, investigators were able to confirm Rhea Rasmussen’s identity. She is believed to have been between 2 and 4 years old when she was killed.

However, Reid remains missing and is believed to have been murdered by Terry Rasmussen, who was later convicted of murdering his girlfriend Eunson John in 2002.

Send us a tip here

William Talbot II

In a first-of-its-kind trial using genetic genealogy testing, William Talbot II was found guilty of murder in the 1987 death of a young Canadian couple, Jay Cook, 20, and Tanya Van Cuylenburgh, 18.

Do you like what you are reading? Find out more about the True Crime Center

William Talbot II, center, is escorted to his seat Friday, June 28, 2019, at the Snohomish County Courthouse in Everett, Washington. William Earl Talbot II was convicted in the 1987 murder of a young Canadian couple, Tanya Van Cuylenburgh and Jay Cook.

Investigators identified Talbot as a suspect after the upload DNA was found at the crime scene To the general genealogy website GEDMatch. The technology pointed to two of Talbot’s cousins, allowing investigators to build a family tree and eventually identify him as the prime suspect.

Investigators used a discarded coffee cup to obtain Talbot’s DNA, which matched evidence found at the crime scene.

Click here to download the FOX NEWS app

This case was the first time genetic genealogy had been used to prosecute a suspect, with prosecutors reportedly using Talbot as an example to demonstrate the power of genetic genealogy testing.

“People will no longer get away with murder when we get this information,” District Attorney Adam Cornell said. according to FOX 13. “If you’re a killer and you’re out there, this office and other law enforcement across the country could come after you.”

Fox News Digital’s Michael Ruiz contributed to this report.