The germs you leave behind might serve as the equivalent of fingerprints, giving forensic scientists a new way to identify who’s been where.

Researchers from the University of Colorado at Boulder say that touching such things as keyboards and computer mice leaves unique bacteria on the objects. They found in a new study that the left-behind bacteria matches the DNA of the people who left it more than it does of other people.

“Each one of us leaves a unique trail of bugs behind as we travel through our daily lives,” study author Noah Fierer, an assistant professor at Colorado, said in a university news release. “While this project is still in its preliminary stages, we think the technique could eventually become a valuable new item in the toolbox of forensic scientists.”

The study was published in this week’s issue of the Proceedings of the National Academy of Sciences.

At the moment, the technique is 70 percent to 90 percent accurate, Fierer said, but he predicted it would rise as technology improved.

And, he added, that though “there are legal restrictions on the use of DNA and fingerprints, which are ‘personally-identifying,’ there currently are no restrictions on the use of human-associated bacteria to identify individuals.”

“This is an issue we think needs to be considered,” Fierer said.

(University of Colorado at Boulder, press release, March 15, 2010)