Investigation Into Nancy Guthrie Disappearance Reaches 100 Days

The investigation into the disappearance of Nancy Guthrie reached its 100th day on Monday with investigators still awaiting results from DNA analysis at an FBI laboratory. Guthrie was reported missing Feb. 1 from her home in Tucson, Arizona. DNA recovered from the residence was first sent to a private laboratory in Florida before being forwarded to the FBI laboratory in Quantico, Virginia, where the work remains ongoing, law enforcement sources told CBS News.

Officials have not publicly detailed the nature of the DNA sample or its precise location in the home. A former FBI supervisory special agent in Arizona said that a strand of hair found near a victim's last known location, such as in a bed, would receive high priority at the FBI laboratory.

The analysis process, which can include building family trees and conducting forensic comparisons, requires extensive time to ensure accuracy. The sheriff stated it would be inappropriate to discuss evidence in order to preserve the integrity of the case and ensure any suspect receives a fair trial.

If the sample is bodily fluid, it would allow for a more complete DNA profile than skin cells, which often produce lower quantities. A full hair follicle containing a root would be more useful than a strand without one. Sources close to the investigation said laboratory techniques can enhance even low-level samples, though the process may take additional time.

Earlier in the inquiry, DNA recovered from gloves found about 2 miles from the home was traced to a restaurant worker with no connection to the case. A spokesperson for the Pima County Sheriff's Department said in a statement that scientific evidence processing and digital media analysis remain ongoing at the 100-day mark.

The department added that investigators are actively pursuing leads and tips and asked the public to come forward with any information.

Video from a doorbell camera captured a person wearing a ski mask, gloves and a backpack at Guthrie's front door on the night she disappeared. The FBI recovered the video from residual data in backend systems and released it publicly on Feb. 10. The agency has not released additional video.

It continues to ask the public to provide any information connected to the case through the FBI tip line. The FBI and sheriff's department have received thousands of tips. Investigators are also reviewing phone data, surveillance video, GPS records, app and cloud data, and social media accounts.

" She asked the public for continued help and prayers to bring her mother home. The FBI is offering a $50,000 reward for information leading to the recovery of Nancy Guthrie or the arrest and conviction of anyone involved. The Guthrie family has offered an additional $1 million reward.

Local Crime Stoppers is providing $2,500 along with a $100,000 donation from a Milwaukee attorney. Investigators continue the work of re-interviewing witnesses, re-examining old tips and following new ones. The retired FBI agent said that while 100 days may feel long to a family, it can still be early in a major investigation.