The Most Common Antigens

Identified by Dr Karl Landsteiner in 1901, the most common antigens are A and B, and a person with type O blood has neither of the antigens, while some have both of them (Type AB).

Another antigen called RhD was discovered in 1937.

Currently, we have 36 systems to categorize blood types and 346 different antigens, whose exact purpose still remains unknown.