Mystery DNA and forensic delays are complicating the investigation into Nancy Guthrie’s disappearance in Arizona.

A strand of DNA. An eerie doorbell video. The investigation into Nancy Guthrie's disappearance reaches 100th day with no sign of a breakthrough.

The DNA sample found in Nancy Guthrie's home is reportedly unable to be entered into CODIS. CODIS or the Combined DNA Index System, is a computer software program that operates local, state, and ...

Hopes were raised when investigators said they found DNA inside the Arizona home of Today show co-host Savannah Guthrie’s mother Nancy Guthrie, who vanished in the early hours of Feb. 1. The DNA found ...

Investigators are still hard at work analyzing DNA and footage related to 'Today' co-anchor Savannah Guthrie's mother's ...