Modern Human Variation: Distribution of Blood Types

The two most common blood type tests are the ABO and Rh tests The ABO test shows which of four blood types you have: A, B, AB, or O These letters stand for

A, B, and AB are all factors that can be present in your blood While there are four types, there are only actually two antigens involved: A and B! AB blood

blood type The Rh factor is inherited independently from the ABO blood type Genotypes for the Rh factor are ++, +-, and -- People who are ++ or +- possess the Rh

blood link The blood types that exist in humans are A, B, AB and O Not all blood types are compatible with each other, however, and therefore it's