A thief wearing gloves walks into a parking lot, perhaps using the cover of night, smashes a car window and takes what's inside the vehicle, all in a matter of minutes.

It's the general technique for many car burglaries, and thousands of them occur in Harris County every year. Besides shattered glass, often there's not much visible evidence left at the scene, leaving investigators with few clues to catch the culprits.

But sometimes it's what investigators cannot see that helps solve many of these types of crimes.

For the last few years, the Harris County Institute of Forensic Sciences aided area law enforcement in solving property crimes by testing evidence for "touch DNA" - microscopic skin cells containing DNA that naturally rub off when an object, like a car steering wheel, is touched. The technology can be used even if the suspect is wearing gloves because there's a high likelihood the skin cells were transferred onto the gloves when the perpetrator was slipping them on.

"It was a pretty incredible tool for us to have to identify some of these suspects," said Sgt. Terry Wilson, of the Harris County Sheriff's Office auto-theft division. "These (burglary of a motor vehicle) cases are some of the hardest cases for law enforcement to solve because there's almost never any eyewitnesses. There's very rarely any good evidence left behind, fingerprint evidence and things like that, and once we started recovering some of this DNA, it was pretty exciting there for a while."

DNA testing is a practice typically reserved for personal crimes like rape and murder. However, the forensic institute, formerly the medical examiner's office, has also been performing DNA testing on evidence - containing either skin cells or bodily fluids, like blood and saliva - from property crime cases such as car break-ins and home invasions.

Thousands of matches

Since January 2008, the forensic institute made more than 3,000 matches to crime suspects in the FBI's Combined DNA Index System database, or CODIS, a national database used to store DNA profiles. Of those, about 75 percent were for property crime cases.

Dr. Roger Kahn, director of the forensic genetics laboratory at the institute, said the crime lab is one of the few equipped to handle DNA testing for property crimes. The lab has no testing backlog on personal crime cases, so it can focus on property crimes, he said.

Kahn noted that when the forensic institute moves to its new expanded facility in the fall, the lab will have the capabilities to perform DNA testing in property crime cases for not only law enforcement agencies in the county, but the entire region.

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Investigators using 'touch DNA' to solve property crimes