Nearly three months after Nancy Guthrie vanished from her home in Tucson, Arizona, a new development in the case is raising more questions than answers, Wonderwall.com can reveal. Recent reports revealed that a DNA sample tied to the investigation has now been transferred to the FBI for advanced analysis. The revelation has sparked criticism over how the evidence has been handled. DNA evidence raises eyebrows DNA evidence in Nancy Guthrie's case was transferred to the FBI after weeks at a private lab.