He can't say how it got there or how long it had been there, but an RCMP scientist was able to extract Chad Davis's DNA from a single drop of blood police found during their search of a garage on Prince Rupert Avenue.
It's the place RCMP and Crown prosecutors allege Davis, 22, was brutally murdered on Feb. 6, 2008 before being placed in a barrel and then dumped in a lake outside Lac du Bonnet.
The garage, located at 703 Prince Rupert Avenue, is where Corey Tymchyshyn lived with his mother around the time Davis, his friend and former roommate, was last seen alive.
Tymchyshyn, 37, and his business partner, Kristopher Brincheski, 31, have pleaded not guilty to first-degree murder.
Jurors were given a crash course in the complexities and process of DNA analysis Friday through Dr. Greg Litzenberger of the RCMP's biology section.
It was Litzenberger who examined and tested several swabs from the garage that forensic officers gathered during a search there between Sept. 7 and 9, 2008 — about six weeks after Davis's body had been recovered from the Lee River and his death declared a homicide.
Litzenberger testified he was able to extract 1.92 nanograms of DNA from one swab of a spot police took off of the garage floor. He compared his findings to a known sample of Davis's DNA.
"The profiles were the same. They matched one another," he said. The statistical probability of the DNA belonging to another Caucasian male plucked at random from the Canadian population was one in 220 billion, Litzenberger said.
How the drop of blood from which the DNA was extracted came to be in the garage, he couldn't say.
"If there was a major bloodletting event … would it surprise you that only one drop of blood would be located?" Crown attorney Brent Davidson asked.
"Not necessarily," said Litzenberger. "Without knowing anything else that happened, you can't make any assumptions on that," he said.
He agreed with defence lawyer Roberta Campbell that no DNA was found on plastic bits seized by RCMP from boards that had been torn out of the Prince Rupert garage and then used in a renovation project in Anola.
The Crown's position is the bits match up to the kind of plastic Davis was found wrapped in when the barrel was recovered.
A toque was also recovered from the garage and found to have bloodstains on it. The DNA from that blood was not Davis's, jurors were told.
The trial resumes Monday.