Investigators were unable to generate a DNA profile from a hair sample collected from Nancy Guthrie's home, Pima County Sheriff Chris Nanos announced Thursday. Despite the setback, Nanos indicated the sample may still be valuable to the ongoing investigation.

"It came back...there's no DNA," Nanos told Fox News Digital. "But does that mean the hair isn't that of the suspect? We won't know that till we have the suspect's hair. You don't just destroy it."

The hair sample was sent to a laboratory in California for testing in collaboration with the FBI. Sheriff Nanos confirmed that investigators have preserved the sample, stating that "there's other things that hair may prove valuable for, but right now it was just about, 'Is there any DNA there?' And the answer was no."

Nancy Guthrie, the 84-year-old mother of "Today" co-host Savannah Guthrie, has been missing for nearly six months. Saturday will mark the six-month anniversary of her disappearance.

Sheriff Nanos emphasized that DNA testing remains a priority, with investigators working with multiple crime labs to analyze evidence collected from the scene. "Anything we can grasp onto with DNA is a part of this investigation," he said. He expressed optimism about the advancements in DNA technology, stating, "That's really where some of my optimism is, that I just know that we're gonna get this thing resolved."

Unclaimed Reward and Suspect Information

A reward of over $1.2 million remains unclaimed for information leading to an arrest. The sheriff's department, along with the Guthrie family, is urging anyone with information to come forward.

"We believe, just as the family does, just as Savannah does, somebody knows something. We need that person to call us."

Surveillance footage from Guthrie's Nest doorbell camera captured at least one suspect. The FBI described this individual as being between 5 feet, 9 inches and 5 feet, 10 inches tall with a medium build. The suspect was wearing a mask, long sleeves, and gloves. The backpack carried by the suspect has been identified as a black Ozark Trail brand bag.

Individuals with information can contact the FBI at 1-800-CALL-FBI. Information that leads to an arrest can be reported to 520-88-CRIME to claim an anonymous reward.