Forensic scientists may soon have a valuable addition to their toolkit. A study published in PNAS 15 March 2010 by Noah Fierer of University of Colorado, Boulder reveals that “personal” bacteria deposited on computer keyboards and mice matched bacterial DNA signatures of users more closely than those of random users.
In a previous study published in PNAS 12 November 2008, Fierer and colleagues identified 4,742 unique bacteria across palmer surfaces of 51 hands of healthy young adult volunteers. A typical hand surface was host to more than 150 unique species-level bacteria. The study revealed pronounced intra-and interpersonal variation in bacterial community composition. Hands from the same individual shared only 17% of bacterial phylotypes, with different individuals sharing only 13%.
In a sense, each of us leaves a unique trail of bugs. While these findings are still preliminary, they offer a real opportunity for forensics experts to independently confirm the accuracy of DNA and fingerprint analyses