People leave molecular wakes that may give away their secrets

GENES CAN tell tales about you, from who your ancestors were to how likely you are to develop a range of diseases. And it seems probable that in the future they will tell more: your personality type, perhaps, or your intelligence. For these reasons, many countries have laws limiting what use employers and insurance companies can make of such information. America, for example, has the Genetic Information Nondiscrimination Act, which makes it illegal for health insurers and employers to use geneti...