THE CLAIM: Identical twins have identical fingerprints.

THE FACTS: Identical twins often share personality traits, interests and habits. They come from the same fertilized egg and share the same genetic blueprint.

To a standard DNA test, they are indistinguishable. But any forensics expert will tell you that there is at least one surefire way to tell them apart: identical twins do not have matching fingerprints.

Like physical appearance and personality, fingerprints are largely shaped by a persons DNA and by a variety of environmental forces.

Genetics helps determine the general patterns on a fingertip, which appear as arches, loops and whorls. An individual finger can have just one of these patterns or a mixture of them.