* Certain blood types are more common in certain countries. In China, over 99% of the population has Rh+ blood.

* Different kinds of animals have different kinds of blood. Dogs have 4 blood types; cats have 11; cows have about 800.

* Some people think blood type tells about personality. Legend has it that Type A is calm and trustworthy; Type B is creative and excitable; Type AB is thoughtful and emotional; and Type O is a confident leader.

* In Japan, the idea of blood type as personality type is so popular that Japanese ask “What's your blood type?” about as often as Americans ask “What's your sign?”