The specialized lab racing to solve the Guthrie disappearance

Based inconspicuously in a quiet building in Florida, one private and secretive laboratory has the power to make or break some of the biggest criminal cases in the country - and may be key to solving the disappearance of 84-year-old Nancy Guthrie in Tucson, Arizona. Scientists at DNA Labs International (DLI) in Deerfield Beach take blood, bone, skin cells and even trace genetic material shipped to them from law enforcement agencies around the country to identify suspects, clear the innocent, and solve crimes that once seemed impossible. DLI was founded in 2004 by a mother-daughter team, Kirsten Charlson and Allison Nunes, who wanted to make sure women and girls who were crime victims did not have to wait too long for DNA results. The pair rarely speak publicly and there's good reason why. Forensic DNA consultant Suzanna Ryan told the Daily Mail that says private labs often remain tight-lipped during active criminal investigations not out of secrecy, but because of strict legal and procedural limits on what they can disclose.

'Private labs … will have a case submission form, and it tells us who we can talk to, and I cannot release information to anyone else,' Ryan, who is also the lab director of Pure Gold Forensics, a private lab in Redlands, California said. 'They certainly can't talk about this case. That's part of it.' DLI examined a glove found in the close vicinity of Guthrie's home in the Catalina Foothills of Tucson that the FBI believes matches the gloves worn by a masked intruder caught on video at her home early in the morning of February 1 when she was abducted. The glove was found around February 12, about two miles from the Guthrie residence in a field near the side of the road. The glove was one of about 16 recovered in the area, according to the FBI, and was immediately sent to DLI for testing. The process itself follows a defined sequence once evidence arrives at a lab. Analysts first document and photograph the item, then collect biological material—sometimes using specialized tools like an M-VAC, a wet vacuum device designed to capture trace DNA. The lab's analysis of that glove was reportedly sent to the FBI on February 14 to run through CODIS, the national database it keeps of DNA profiles, to compare it with other DNA profiles from crime scenes, convicted offenders and missing persons. However News Nation quoted an FBI official late Friday saying the DNA sample may still be at the Florida lab.

If the DNA in the glove does not match anyone on file in the CODIS database, Pima County Sheriff Chris Nanos said it doesn't mean that that DNA is useless. 'If he's not in the file base, we're still kind of stuck,' Nanos told the Daily Mail. 'But it doesn't mean it's over. Take the individuals we stopped last week. We can do a petition for physical characteristics, (which is) basically a search warrant on that individual to give us his buccal cells and whatnot. Once we have those, we can compare them. I really think some of the DNA we have that we haven't been able to eliminate, maybe it's Nancy's or whatever, that will come when we actually have the right person.' DLI also deploys forensic genetic genealogy - a powerful tool that can identify suspects by tracing their DNA through relatives, even distant cousins. 

The same cutting-edge method was used to link the DNA found on the knife sheath left behind by Bryan Kohberger to his family, ultimately leading to his arrest for the brutal murders of four college students in Moscow, Idaho, in November 2022. By the time a lab's role becomes public, the genetic work is usually long finished, DNA consultant Ryan added. 'Not many cases where everybody knows what lab is actually conducting the DNA testing as it's happening in real time. Usually the testing is already done, and then it's reported, 'Oh, we have a match.' So this is a little bit unique.' DNA testing has transformed criminal investigations over the past several decades. Ryan said early methods required large, pristine samples and weeks or months of analysis. The first DNA testing widely used in US courts relied on a technique known as RFLP, first tried in Florida in 1987. That method was revolutionary but limited. 't would take months to do, and you had to have a really large sample size,' she said. 'It couldn't be broken down or degraded in any way.' Modern testing, by contrast, is far faster and more sensitive.

Polymerase chain reaction, or PCR, allows analysts to amplify small amounts of DNA. Current short tandem repeat, or STR, analysis examines many specific locations on the DNA molecule to distinguish individuals. 'Instead of having to have this really large amount of very pure DNA, now we could start with a much, much smaller amount,' Ryan said. 'We need like 10 cells and we can get a DNA profile, whereas before we were talking a blood stain the size of a quarter.' This cutting-edge science involving microscopes and sequencing machines taking aim at high-profile criminal mysteries can often seem ripped from a 'CSI' type TV show. But there is some growing controversy over the expanding power of the private forensic labs. DLI represents the new frontier of criminal investigation, where private companies wield powerful technology capable of solving crimes once thought unsolvable. At its core, DLI functions as a high-tech partner to police departments, prosecutors, and defense attorneys. Using tools like whole-genome sequencing and SNP analysis, which are techniques capable of extracting genetic clues from degraded or decades-old evidence, the private forensic labs help investigators turn cold cases into solved cases.

DLI's website details just a few of the cold cases it has cracked: DLI Labs used forensic genealogical data to nail Brian Leigh Dripps as the killer of Angie Dodge, who was kidnapped and raped at age 18 in Idaho in 1996 . The true perpetrator was caught 23 years later with what is called 'autosomal familial searching.' A man who served 20 years in prison for the crime was exonerated and released. DLI helped extract and analyze degraded DNA in the cold case of someone known only as 'Buckskin Girl,' named only for her jacket, whose body was discovered in Ohio in 1981 . DLI helped lead investigators to identify her as Marcia King, a 21-year-old from Arkansas who vanished years earlier. In 1957, the body of a young boy was found abandoned in a cardboard box in Philadelphia and was known as 'The Boy in the Box.' DLI Labs helped analyze preserved genetic evidence that had been preserved - and identified him as Joseph Zarelli in 2022. While effective, the methods used by these forensic crime labs has sparked civil liberties concerns because it can implicate individuals who never submitted their DNA to law enforcement.

Critics argue it blurs the line between investigative tool and genetic surveillance - and they also claim that the government should not necessarily be outsourcing crucial data to private companies. Ryan pushed back on the criticism. 'Private labs are held to the exact same standards,' she said. 'We are accredited, the same guidelines and the same audit documents. We have people coming into our lab to ensure that we're following those standards. Most of the research and the ability to quickly implement new technology—that's usually the private labs,' she added. 'Private labs are used extensively and routinely … typically faster and typically have more advanced techniques than many of the state and county labs.' Supporters say the labs helps bring justice to victims and closure to families - and help bring the bad guys to justice. 'Criminals have a much tougher path these days,' Ryan said.