As the investigation into Nancy Guthrie’s disappearance reaches its 100th day, a critical piece of evidence—a DNA sample taken from her Arizona residence—is currently undergoing thorough examination at the FBI’s crime lab. Authorities remain hopeful that this development could provide a significant breakthrough in the case.
Initially, the DNA sample from the 84-year-old’s home was sent to a private laboratory in Florida by detectives from the Pima County Sheriff’s Office. This step was taken despite the FBI’s earlier offer to conduct the analysis using their cutting-edge resources.
It was only several weeks after Nancy’s abduction that the crucial evidence was handed over to federal investigators for more advanced testing.
While specific details about the type of DNA or its exact location within the home have not been disclosed, law enforcement sources have confirmed to CBS News that the analysis is ongoing.
According to retired FBI special agent Jason Pack, the process of DNA analysis—which can involve constructing entire family trees to pinpoint potential suspects—is far more time-consuming than the swift resolutions often portrayed in television crime dramas.
“This meticulous work requires time because accuracy is paramount,” Pack explained to the news outlet.
“An item containing DNA, such as a strand of hair found somewhere in a house, is one thing, but a strand of hair near the victim’s last known location, such as in her bed, would be a high priority for the FBI,” Lance Leising, an ex-FBI special agent in Arizona, added.
Pima County Sheriff Chris Nanos, who has been ridiculed for bungling DNA evidence and shutting the federal agency out of the high-profile probe early on, refused to comment about the sample still being analyzed.
“It would be highly inappropriate of me to speak to the evidence. We have to keep the integrity of this case,” he said.

“If we make an arrest, that individual has the right to a fair trial, I can’t sit here and address all of that.”
“We are working hard with all of our partners to resolve this case, and we will,” he added.
It comes as the search for “Today” show host Savannah Guthrie’s mom hit the 100-day mark on Monday.
Nancy is believed to have been taken from her Tucson home in the early morning hours of Feb. 1.
Chilling security footage later recovered from her doorbell camera captured a masked man loitering around her doorstep the night police believe she was kidnapped.
Blood spatters were later discovered on her front door step.
As the search for the grandmother surpassed its 100th day, investigators still hadn’t determined any credible leads or suspects in the case.