Authorities investigating the disappearance of 84-year-old are facing 'challenges' with DNA evidence recovered from her Arizona home, with Pima County Sheriff Chris Nanos warning it could take up to a year for a private laboratory to fully analyse the samples.
Nanos said tests carried out so far have produced incomplete and mixed DNA profiles which do not match Guthrie, her relatives or people known to have worked in the property, complicating efforts to identify any unknown individuals who may have been inside the house.
