The FBI has DNA from inside Nancy Guthrie's home. Investigators believe it may belong to the person who took her. And yet - more than six weeks later - they still cannot use it. Here is the reason why.
Genetic genealogist CeCe Moore, who has helped solve more than 300 cold cases using DNA evidence, sat down with NewsNation's The Truth of the Matter podcast this week and gave the clearest explanation yet of why this critical piece of evidence remains locked - and why it could stay that way for up to a year.
What is the problem with the DNA?
The DNA recovered from inside Nancy Guthrie's Tucson home is what forensic scientists call a mixed sample - meaning it contains genetic material from more than one person. That mixture makes it nearly impossible to isolate a single profile and run it through national databases like CODIS.
Moore explained that when she first heard the evidence was a mixed sample, she was not immediately alarmed. "In some cases, that can be positive because it can give you a better idea that you're actually working with the DNA from the perpetrator," she said. But as weeks passed with no results, she began to suspect the mixture was far more complex than initially thought.
Why can't existing technology solve it?
This is where the case hits a wall that no amount of investigative urgency can break through.
Moore was direct: the software needed to "deconvolute" - or separate - the individual DNA profiles within this specific mixture does not currently exist, at least not in a form the FBI or specialized labs can access. "The way I interpret that," she told host Natasha Zouves, "means they don't currently have the ability to separate it, and they're hoping that the science is going to advance."
Sheriff Chris Nanos confirmed that the sample presents real challenges and that resolving it could take up to a year. That is not a delay caused by a backlog. It is a delay caused by the limits of science itself.
Investigators also cannot simply turn to large consumer databases like Ancestry or 23andMe due to privacy restrictions - limiting them to smaller opt-in platforms like GEDmatch, which significantly narrows the pool of potential matches.
Is there any reason for hope?
Despite the roadblock, Moore was careful not to close the door entirely.
"That's not to say that there isn't somebody out there who is developing something, or has developed something that would work," she said. "Hopefully this will spur on even more innovation and give new scientists the opportunity to present maybe something they've been working on."
She also pointed to a scenario that could bypass the DNA problem entirely - a second crime scene. If Nancy was taken somewhere after leaving her home, both she and her abductor would have left fresh DNA behind. "We leave DNA everywhere," Moore said. "Nancy would have left DNA everywhere she was taken, and the perpetrator would have as well. It's just a matter of finding that."
Moore also made a direct appeal to the public - urging anyone who has taken a consumer DNA test with AncestryDNA, 23andMe, or MyHeritage to download their raw data and upload it to GEDmatch or FamilyTreeDNA. Those are the only databases law enforcement can legally access. That one step from an ordinary person could be the breakthrough investigators have been waiting for.
Where the case stands today
As of March 17 - Day 45 of Nancy Guthrie's disappearance - no suspect has been named, no arrests have been made, and her whereabouts remain unknown. The Guthrie family's $1 million reward remains active. The FBI has received more than 13,000 tips. A glove found two miles from Nancy's home was tested but traced to a local restaurant worker with no connection to the case.
Savannah Guthrie has said her family is "blowing on the embers of hope." Science may be racing against time - but the prayers, the tips, and the search have not stopped.
If you have any information, contact the FBI at 1-800-CALL-FBI or submit a tip at tips.fbi.gov.
