Retired FBI agent unpacks ‘painstaking’ DNA analysis process in Nancy Guthrie case
Retired Supervisory FBI Agent Jason Pack told Fox News Digital on Friday that there is “painstaking, precise work” happening involving DNA collected in the Nancy Guthrie disappearance.
Pack pointed to biological evidence recovered from inside Guthrie’s residence in Tucson, Arizona, that is currently being processed at a private out-of-state lab.
“It was collected early in the investigation. But separating individual DNA profiles from a biological mixture is painstaking, precise work. It cannot be rushed,” he said.
“When the private lab finishes, those completed DNA profiles go back to the Pima County Sheriff’s Department. From there, the FBI takes the profiles and uploads them into CODIS. Within a short window after that upload, investigators will know whether there is a hit,” Pack continued. “If a profile matches a known offender in the national database, the investigation changes direction almost immediately.”
“At the same time, investigative genetic genealogy is running as a parallel track,” he added. “Instead of looking for an exact match to a known offender, genealogy analysts upload the DNA profile to commercial databases and search for partial matches, relatives who share enough DNA to help map a family tree and work toward identifying the unknown contributor. It is slower and more complex than a CODIS hit, but it has identified suspects in cases where traditional database searches turned up nothing. Both tracks are running simultaneously. Investigators do not have to choose one over the other.”
Pack also mentioned that DNA recovered from a glove found about two miles from Nancy Guthrie’s home is being investigated as well.
“Both tracks are running simultaneously. Investigators do not have to choose one over the other. Think of it this way: the glove DNA, If relevant, puts someone in the neighborhood. The residence DNA could put someone inside the house. Those are two very different things in a court of law and in an investigation,” Pack told Fox News Digital.
He said the DNA profiles in the private lab “may be the closest thing investigators have to a name.”
“Everything is waiting on the science to finish,” Pack concluded. “And while Investigative Genetic Genealogy night be the road forward, the Guthrie family could sure use a short cut. Those usually show up in a tip from the public.”
