Your cell phone holds secrets about you.
Besides the names and {{U}} {{U}} 1 {{/U}} {{/U}}that you've
programmed into it, traces of your DNA linger on the device, according to a new
study. DNA is genetic material that {{U}} {{U}} 2
{{/U}} {{/U}}in every cell. Like your fingerprint, your DNA is unique to
you—{{U}} {{U}} 3 {{/U}} {{/U}}you have an identical twin.
Scientists today routinely analyze DNA in blood, saliva, or hair left {{U}}
{{U}} 4 {{/U}} {{/U}}at the scene of a crime. The results often help
detectives identify {{U}} {{U}} 5 {{/U}} {{/U}}and their
victims. Your cell phone can reveal more about you {{U}} {{U}} 6
{{/U}} {{/U}}you might think. Meghan J. McFadden, a scientist
at McMaster University in Hamilton, Ontario, heard about a crime in which the
suspect bled onto a cell phone and later dropped the {{U}} {{U}} 7
{{/U}} {{/U}}. This made her wonder whether traces of DNA lingered on cell
phones-even when no blood was involved. {{U}} {{U}} 8 {{/U}}
{{/U}}she and colleague Margaret Wallace of the City University of New York
analyzed the flip open phones of 10 volunteers. They used swabs to collect
{{U}} {{U}} 9 {{/U}} {{/U}}traces of the users from two parts of
the phone: the outside, where the user holds it, and the {{U}} {{U}}
10 {{/U}} {{/U}}, which is placed at the user's ear.
The scientists scrubbed the phones using a solution made mostly {{U}}
{{U}} 11 {{/U}} {{/U}}alcohol. The aim of washing was to remove all
detectable traces of DNA. The owners got their phones {{U}} {{U}}
12 {{/U}} {{/U}}for another week. Then the researchers collected the
phones and repeated the swabbing of each phone once more. The
scientists discovered DNA that {{U}} {{U}} 13 {{/U}} {{/U}}to
the phone's speaker on each of the phones. Better samples were collected from
the outside of each phone, but those swabs also picked up DNA that belonged to
other people who had apparently also handled the phone. {{U}} {{U}}
14 {{/U}} {{/U}}, DNA showed up even in swabs that were taken
immediately after the phones were scrubbed. That suggests that washing won't
remove all traces of evidence from a criminal's device. So cell phones can now
be added to the {{U}} {{U}} 15 {{/U}} {{/U}}of clues that can
clinch a crime scene investigation.