Nancy Guthrie Update: Why It Could Take A Year To Identify The 'Complex' Samples

Authorities investigating the disappearance of 84-year-old are facing 'challenges' with DNA evidence recovered from her Arizona home, with Pima County Sheriff Chris Nanos warning it could take up to a year for a private laboratory to fully analyse the samples.

Nanos said tests carried out so far have produced incomplete and mixed DNA profiles which do not match Guthrie, her relatives or people known to have worked in the property, complicating efforts to identify any unknown individuals who may have been inside the house.

Outlining 'Challenges' With Samples

Speaking to NBC News, Nanos said DNA obtained from Guthrie's home is partially combined with the 84-year-old's own genetic material and is proving difficult to separate into clear, usable profiles.

'Our lab tells us that there's challenges with it, and we understand those challenges,' he said. 'But our lab also knows that the technology is moving so fast and in such a frenzy that they think some of this stuff will resolve itself just in a matter of weeks, months or maybe a year, to allow them to do better with, say, a mixture of that kind of thing.'

According to Nanos, local law enforcement initially processed the samples, but a private laboratory in Florida is now working to further analyse the material. It is not clear why investigators opted to rely on that facility rather than using federal resources such as FBI laboratories or Arizona's own Scientific Analysis Bureau.

The sheriff's comments underline the growing reliance of complex investigations on advanced forensic technology — and the strain that delays can place on families waiting for answers. Mixed or degraded DNA samples can require more sophisticated techniques and repeated testing before any meaningful conclusions can be drawn.

Sheriff Believes Nancy Is Still Held Locally

Guthrie, who is the mother of NBC Today co-anchor Savannah Guthrie, was reported missing from her Tucson-area home, prompting a multi-agency search effort and extensive media coverage in the United States and abroad.

The FBI is assisting the Pima County Sheriff's Department by reviewing digital evidence, including data, video and interview material, as part of the continuing search for the missing 84-year-old. However, despite the release of surveillance footage showing a potential subject, investigators have not yet identified any suspects.

'Officials still do not have suspects or a list of names,' Nanos said, adding that leads generated so far had not yet produced a clear person of interest.

In a separate interview with the BBC on Wednesday 18 February, the sheriff said he believes Guthrie is still in the local area, while stressing that this view is not backed by hard evidence.

'I don't know why. I don't have any evidence to prove that, but I just believe she's somewhere here locally,' he said.

Nanos has acknowledged public frustration at the pace of the investigation and the time it is taking to secure forensic results.

'It's never fast enough for the sheriff. I want it like you, "Come on, guys, let's go, let's go, let's find her",' he told NBC News, referring to the pressure he feels to deliver progress in the case.

DNA's Absence Key Focus for Authorities

The apparent absence of a clear DNA match to family members or known associates inside Guthrie's home is likely to be a key focus for detectives as they try to reconstruct who may have entered the property and under what circumstances.

However, until the mixed samples can be fully separated and interpreted, investigators are limited in what they can conclude from the genetic evidence.

Law enforcement officials have not publicly commented on any working theory about Guthrie's disappearance. Previous reports have included suggestions that the incident might be linked to a burglary, but authorities have not confirmed the nature of the suspected crime or whether they believe she is being held against her will.

For now, the case remains open and active, with local deputies and federal agents continuing to gather information while the Florida laboratory works through the 'complex' DNA profiles — a process that may take months before producing any breakthrough.