DNA pet detectives

We've all seen high profile court cases or TV dramas where DNA evidence saves the day.  Now, the science is going to the dogs.  More and more, people are turning to high tech evidence to solve all kinds of cases involving animals.  Whether it's to find a missing pet or solve a vicious attack.

Dr. Janice Sojka teaches Animal Forensics at Purdue University and says DNA samples can be obtained from hair, saliva or even things like chew toys.  You can call your vet for help in determining how to get samples which may then be sent to a specialized veterinary genetics lab like the one at UC Davis.  There's a huge range of sample types and samples that come to the lab.  And the DNA is tested for all kinds of cases.

"Anything that can be done for human DNA could theoretically be done for animal DNA," said Dr. Sojka.  "They don't have to have a suspicion about what animal was responsible for something, they can absolutely prove it."

When Ryan Armstrong was only seven years old, his thumb was nearly torn off and his chest punctured by a loose Rottweiler.  "If you saw your child laying there all tore up, was this close to death, I think now you need to know who did it, who's responsible for this?"  Ryan's dad, Jeff, worked for years to find the dog but got nowhere until experts suggested comparing DNA on the jacket Ryan was wearing to saliva from two dogs in the area. After testing two dogs in the area against Ryan's jacket, the lab found a match.  Ryan's dad says he was relieved to finally get justice, "The owner was arrested, charged with having a dangerous dog."

"Sometimes it involves stolen animals," says Dr. Elizabeth Withcum, also from UC Davis.  "Another scenario is when the animal is actually the perpetrator such as dog attacks on other pets."  That's what happened to Marylin Christian who was heartbroken after her cat Cody was killed right in her backyard.

She was devastated but determined to find the killer. "We have other small animals as well as children," Christian said.  "So, we wanted to make sure that our family was safe, two legged and four legged."

Marylin believed a neighbor's dog was to blame, but without an eyewitness she was at a loss.  "It was the vet that suggested using the DNA.", she said.  She went ahead with the test, comparing the DNA of the suspected dog's saliva to hairs found on Cody.  The lab confirmed her suspicions telling her there was only a 1 in 67 million chance that the hairs belonged to a dog other than her neighbor's.  Shortly after Marilyn got the results, the animal's owner moved away.

The DNA testing ranges from $500 to $1000 and the results can take anywhere from two to twelve weeks.  You must get permission or a court order to collect DNA samples from an animal other than your own.  And, if you are taking a sample like saliva from an animal deemed dangerous, it's important to have a professional obtain the DNA for you.