Bryan Kohberger's DNA matches evidence found at Idaho murder scene: Court docs

A cheek swab taken from Bryan Kohberger is a statistical match to DNA evidence found at the Moscow, Idaho, crime scene where four University of Idaho students were murdered late last year, according to new court documents.

Kohberger,a 28-year-old criminology Ph.D. student at Washington State University, is accused of fatally stabbing Ethan Chapin, 20; Madison Mogen, 21; Xana Kernodle, 20, and Kaylee Goncalves, 21.

Investigators found a Ka-Bar knife sheath on the bed with the bodies of Mogen and Goncalves. The sheath was face down, partially under Mogen's body and the comforter on the bed, according to court documents.

DNA evidence was found on the Ka-Bar knife sheath that came from a single source that was male.

After assuming the investigation from Idaho State Police, the FBI submitted the possible suspect DNA to publicly available genetic genealogy services to determine potential relatives of the suspect. The FBI then used common genealogical techniques to develop a family tree that led to Kohberger.

The DNA was 5.37 octillion times more likely to be Kohberger's than a random person from the general population, according to the documents.

Law enforcement previously said they had obtained DNA from the knife sheath and matched it to DNA from Kohberger's father found in the trash outside the family home. Now, the new documents show a match directly from a cheek swab taken from Kohberger.

Kohberger, was arrested at his parents' home in Pennsylvania's Pocono Mountains on Dec. 30. Kohberger, who was arrested on four counts of first-degree murder and burglary, has been extradited from Pennsylvania to Idaho. He is being held awaiting trial.

The judge entered a not guilty plea on Kohberger's behalf last month.

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