WASHINGTON (AP) — Sorry, clean freaks. No matter how well you scrub your home, it’s covered in bacteria from your own body. And if you pack up and move, new research shows, you’ll rapidly transfer your unique microbial fingerprint to the doorknobs, countertops and floors in your new house, too.

In fact, researchers who studied seven families in Illinois, Washington and California could easily match up who lived where using their microscopic roommates, almost like CSI for germs.