A 15 year old US boy conceived by an anonymous sperm donation has traced his father by using the Internet, including an online genealogy DNA-testing service.
This demonstrates the power of biometrics: identification of an individual; but also its weakness: the same online data makes biometric information public, and therefore of very limited use in authentication. There is a tendency to think of a biometric as a “shared secret” when, in reality, it is a difficult-to-forge identifier.