The investigation into the disappearance of Nancy Guthrie, mother of NBC's Savannah Guthrie, has taken a concerning turn as the FBI resorts to advanced DNA technology. A professor from the University of California, Los Angeles, noted that the FBI's decision to use new forensic techniques indicates they are struggling to find new leads. The FBI has received a mixed DNA sample from Nancy's residence in Arizona, which poses challenges in isolating usable profiles. Pima County Sheriff Chris Nanos acknowledged these difficulties, stating that results could take 'weeks, months, or maybe a year.' Experts emphasize that the reliance on older evidence suggests that initial leads have gone cold, and the agency is now attempting to extract more information from existing samples. The investigation also involves reviewing thousands of hours of video footage to gather further insights.