BOULDER, Colo. -- You really do leave a piece of yourself behind, every time you touch something.

Scientific researchers at the University of Colorado at Boulder believe they’ve found a way to identify people based on the unique bacteria we each carry on our skin.

“You’re going to harbor a lot of the same bacteria that you have on your skin,” said Dr. Christian Lauber, research scientist, noting only 13 percent of people have shared bacteria. “So about 87 percent of the bacteria you have, at least on your palm, is unique to yourself.”

In just three weeks, the team used new, advanced DNA sequencing technology to identify the users of three computers, using cotton swabs to collect samples from the keyboard and mouse.

They were able to pinpoint the “donor” of that bacteria, which showed more similarities than the others out of a pool of 270 people.

Unlike so-called human DNA collected from hair or blood, Lauber said, this bacterial fingerprint can change a bit over time.

“This is a little more transient and you know, another area that has to be researched before it would even be allowed in a courtroom.”

But there is excitement that this could be another tool law enforcement could eventually use.

"The concentration of DNA present from bacteria may be higher (more cells to glean DNA), and the DNA may be less likely to degrade due to its circular nature. Therefore it may be easier to detect and develop useful profiles versus what a situation where trace amounts of DNA may not be detected from an individual due to brief contact with a surface. Certainly this must be further investigated, " said Ronald Arndt, Agent in Charge of the Biological Science Unit at the Colorado Bureau of Investigation. "There must be research done to determine the statistical significance of any type of association between a person and the object tested. Therefore, there must be extensive validations done as well as development of standard protocols, kits and the like before it can be considered of possible value to the forensic community," Arndt said.

“Even though our similarity and success in matching a mouse or a surface to a hand was pretty good, it’s still not good enough for any kind of forensic application yet. But it does tell us the bacteria on our hands remain or they keep that unique signature on a lot of surfaces,” Lauber said.

Their findings were published Monday in a biweekly publication called Proceedings of the National Academy of Sciences.

Lauber said they still have much to learn, like how hard it might be to isolate bacterial signatures from public facilities like library computers or door handles.

“We know it’s got to be more that just walking by and simply brushing an object, but as far as how long you have to handle an object before you leave enough bacteria on there to get a useful comparison we don’t know,” Lauber said.

Not all bacteria is bad, Lauber said, noting that women carry 50 percent more bacteria on their skin than men.

Researchers also believe that even after thoroughly washing your hands, unique bacteria on your skin comes back in about two hours.