Theinvestigation into the disappearance of Nancy Guthriehas taken a significant turn after authorities confirmed they are deploying a forensic strategy once used to identify the killer behind the Idaho student murders. Nancy Guthrie, an 84-year-old Arizona resident and the mother of broadcast journalist Savannah Guthrie, vanished from her home in Tucson on 1 February 2026 under circumstances investigators have described as a likely abduction.

The development has drawn renewed attention to how modern DNA techniques are reshaping major criminal investigations and how a tool that exposed one of America's most closely followed killers may now hold the key to a separate and equally troubling case.

Weeks into the inquiry, law enforcement officials have confirmed they are turning toinvestigative genetic genealogy, the same forensic tool that helped identify Bryan Kohberger as the perpetrator in the 2022 killings of four University of Idaho students. Authorities in Pima County confirmed thatDNA recovered during the investigationhas so far failed to produce a match in the Combined DNA Index System (CODIS), the national database used to compare crime scene samples with profiles from convicted offenders.

The key piece of evidence came from a pair of gloves discovered roughly two miles from Guthrie's residence. Investigators believe the gloves may be connected to a masked individual captured on a doorbell camera tampering with security equipment outside the property on the morning of her disappearance. The DNA profile extracted from the gloves produced no match in the national database, forcing investigators to pursue a more advanced forensic pathway.

Officials said the case will now incorporate investigative genetic genealogy, a method that analyses DNA and compares it against large genealogical databases to identify relatives of an unknown suspect. Authorities have confirmed that additional biological evidence collected from the property is also undergoing further testing.

New images in the search for Nancy Guthrie:Over the last eight days, the FBI and Pima County Sheriff’s Department have been working closely with our private sector partners to continue to recover any images or video footage from Nancy Guthrie’s home that may have been lost,…pic.twitter.com/z5WLgPtZpT

The decision to use investigative genetic genealogy has drawn direct comparisons with the investigation into the murders of four University of Idaho students in November 2022. In that case, authorities discovered a knife sheath at the crime scene containing trace DNA. When the profile did not immediately identify a suspect, investigators used genealogical analysis to build a family tree linked to the unknown sample.

The analysis ultimately led detectives to Bryan Kohberger, a criminology doctoral student who was arrested and charged with the killings. Court documents revealed that investigators obtained rubbish from Kohberger's family home in Pennsylvania and matched the DNA to his father, establishing a familial connection to the crime scene evidence. Kohberger pleaded guilty in July 2025 to four counts of first-degree murder and one count of felony burglary, and was sentenced to four consecutive life terms without the possibility of parole.

Geneticist Ruth Ballard, who specialises in DNA analysis and has testified in hundreds of criminal cases, told the Associated Press that the technique could yield results quickly in the right circumstances. 'If it's a good quality sample and they're able to get a profile, they could find a hit on that fairly quickly,' she said.

As the search for Guthrie continues, investigators have also faced a surge of online speculation surrounding potential suspects. During a recent investigative broadcast on YouTube, journalist Brian Entin highlighted how social media users had attempted to identify individuals appearing in surveillance footage linked to the case. One man was widely accused online after viewers claimed he resembled a masked figure seen near Guthrie's home.

Source: International Business Times UK