BOISE, Idaho — Tuesday, Idaho News 6 reported on the release of DNA information in the investigation of Bryan Kohberger, charged with the November 2022 murders of four University of Idaho students.
The affidavit discusses the link between DNA found on the knife sheath found at the crime scene and the DNA retrieved from a cheek swab of Kohberger after his arrest.
The prosecution says DNA searches in Codis using the STR (short tandem repeat) analysis were unable to generate a match to DNA found on the sheath.
Once the DNA recovered from the sheath was tested against Kohberger's cheek swab, the profile findings were said to be "at least 5.37 octillion times more likely to be seen if Defendant is the source than if an unrelated individual randomly selected from the population is the source," according to information in the motion for protective order filed June 16.
“Those numbers are not like the force of gravity or E=MC2, they’re calculations that give us some idea of the weight of the match, the confidence, but this is a very strong match," said DNA expert and Boise State professor Dr. Greg Hampikian.
Hampikian is not affiliated with the case and only knows what the public does. He says DNA can tell us a lot, but not always the full story.
“Did he touch this? Did somebody else touch it with his DNA on their hand? Did he touch it a long time ago? Was there a mix-up in the laboratory or by the police? Did somebody plant it?" Hampikian said, offering hypothetical situations of how DNA can show up in places. "All of that, DNA tells us nothing about."
The affidavit also talks about how Kohberger was first identified as a suspect. The investigators used a genealogy service, one like popular family tree tracking services, like Ancestry.com or 23-and-me.
The investigation on DNA, then turned over to the FBI, utilized a technique known as Investigative Genetic Genealogy (IGG) using an SNP (single nucleotide polymorphism) profile. The information learned during IGG was only used to establish familial relations.
The IGG information is only used as a tool to develop a possible lead to a suspect.
The prosecution says the lead pointed toward potential relatives of Kohberger, and investigators were able to create a family tree, leading them to find Kohberger.
“To say it’s [geneaology mapping] publicly available to me is misleading at best," Hampikian said. "The police have special use of these databases. They can use the databases in a similar way that I can, but I can only do it for my DNA. They can do it for your DNA.”
Hampikian says he is concerned about the use of these genealogy services in this way. He wants the public to be aware that their DNA could be used by authorities when they submit it to these companies.
“I just hope that we are going to find out how the genealogy was done," Hampikian said. "They can blank out the names of people, but I think transparency about how the leads were generated is really important for the general public to know because they’re being used for this.”
