Lab Uses Pet DNA to Track Down Killers, Solve Cold Cases

Animal cruelty, dog-fighting, horse-dumping. These are cases in which animal evidence is key to solving the crime. But it can be a valuable tool for investigators who are trying to solve crimes against people as well.

The lab that's at the cutting edge of veterinary genetics is just about an hour from the Bay Area. NBC Bay Area's Kris Sanchez takes us there and shows us how pets have already helped crack some California cases.

Man’s best friend… unless that man is a criminal. Then “Fido” could be his undoing. Dog hair, saliva, even a little bit of No. 1 or No. 2 could link a criminal to a crime scene.

“We’ve tested everything,” said Elizabeth Wictum, director of the UC Davis Veterinary Genetics Laboratory. “Investigators will call and say, ‘Bet you’ve never seen this,’ and it’s like, ‘Yeah, we have.’”

Inside a set of unassuming trailers on a country road, Wictum’s forensic unit is the only one accredited to do DNA testing on cats and dogs. Because of stringent standards, Wictum has been called to testify in more than two dozen criminal cases, like that of 23-year old Dane Williams, who was drugged and killed. His body was found dumped in a San Diego alley wrapped in a blanket in 2008.

“They collected some dog hairs from that blanket and we were able to match those hairs to his mother’s dog,” Wictum said.

In that case, the dog DNA link to killer Philong Huynh was indisputable, and he was convicted.

“We got the nuclear DNA on the hair that individualized,” Wictum said, “and when you get that type of DNA, the odds of another dog having that DNA profile is one in quadrillions, just like in human beings.”

That was nuclear DNA, which came from the root of the hair, but which can also come from saliva on that hair, a food bowl or toy, for example. Mitochondrial DNA is less definitive but can still include -- or exclude -- a suspect.

And, DNA is stabe, so it’s usable long after the crime scene’s gone.

When Linda and Steven Riley of Sacramento were violently stabbed 19 times each in their own home, the killer -- their own son -- threw some of the evidence onto the roof, where it sat for a year.

“Those were some animal hairs, dog hairs that were found in some shoes up on a roof,” Wictum said. “They’d been sitting out on the sun up on a rooftop for a year in Sacramento. … We were able to say, yes, those dog hairs could’ve been from that dog.”

Wictum says part of her job as a pioneer in animal DNA is to persuade investigators to collect animal DNA, because it’s everywhere, it’s less expensive to analyze than human DNA, and because it’s so new there is not a backlog. Results are usually available within two weeks.

“They don’t always think of it first, but I’d like for it to be one of the routine tools that they go to in their toolbox,” Wictum said.

The lab developed animal DNA testing with practical applications as well.

The three-woman team created "Meat ID,” which you can use to make sure the meat you pay for is the meat you actually get on your plate.

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