India, May 3 -- Nancy Guthrie remains missing, three months after her family reported the case on February 1. Authorities believe she was taken from her Catalina Foothills home near Tucson, Arizona, the night before. Amidst this, a former FBI agent has suggested that a key piece of evidence recovered from Guthrie's home could help move the case along.

The Pima County Sheriff's Department, which is lead on the case, and the FBI, who are assisting, have not publicly announced any suspects thus far. The closest thing that has been released, is footage of a masked man at Guthrie's home. ABC News reported last month that 'potentially critical' DNA evidence, a hair sample, recovered from Guthrie's house was in FBI hands. Notably, reports at th...