India, Feb. 22 -- Nancy Guthrie's kidnapping case appears to have suffered a setback. The DNA evidence, which was a promising forensic lead might not be yielding results anytime soon. Pima County Sheriff Chris Nanos was speaking to NBC News when he outlined the troubles in the way.

As per Nanos, the lab is having trouble isolating 'mixed DNA samples'. Nanos' office meanwhile said that the samples are still being analyzed. This comes after DNA evidence from Guthrie's house and from a glove found near her home were sent for testing. They initially did not throw up any matches on CODIS, but investigators were leaning towards investigative genetic genealogy for results.

However, Nanos' interview has dampened some hopes. "Our lab tells us th...