What is touch DNA? Go inside the lab that cleared the Ramseys with CNN's Brian Todd

Brian Todd
CNN Correspondent

We tracked down the lab that handled the new kind of DNA evidence that exonerated John and Patsy Ramsey in the murder of their daughter 12 years ago, six-year-old beauty queen JonBenet.

We wanted to find out how this lab effectively ruled out the heart-breaking and unresolved accusations that these parents murdered their daughter.

The lab's run by Bode Technology, based in one of those unassuming office parks - this one in Lorton, Virginia.

When we got there, the photojournalists and I were required to have our own DNA swabbed… two mouth samples each. They say it’s policy, to make sure there’s no strange outside DNA they can’t identify in there.

A funny aside: while we were moving around and filming, someone remarked on the multitude of precautions, and a Bode official quipped, "You should know… everyone who works here has OCD" - Obsessive Compulsive Disorder.

The "touch-evidence" DNA technology that Bode used in the Ramsey case for the first time has actually been around for 4 or 5 years, they tell us, but it’s only been in widespread use for about a year.

Bode handles standard (fluid-sample) DNA testing, too. They have contracts with state, local, and federal law enforcement agencies for that. The cases they’ve been involved in are impressive: not only the Ramsey case, but also helping to identify victims of the World Trade Center collapse on 9/11, missing persons cases in the Mexican drug-wars along the border, and people missing after Hurricane Katrina.

One thing they showed us that they didn’t want publicized in detail - how they clean crime scenes of extraneous DNA that could either dilute the DNA they’re looking for, or contaminate what they have. They let us film it, but said they’d prefer we didn’t use that–because they don’t want to give criminals any ideas.