In the name of science, 2,500 people have participated in Harvard’s Personal Genome Project, anonymously sharing DNA data along with such information as histories of depression and sexually transmitted disease. But Harvard Privacy Lab director Latanya Sweeney demonstrates what “anonymous” really means. Of 579 participants who listed their birth dates, ZIP codes, and genders, her team was able to identify 42% by name using public records. Previously she was able to identify up to 87% of the U.S. population with just ZIP code, birth date, and gender.