What are the blood groups for human beings?
As far as I am aware it is the RhD and ABO blood groups that matter with blood donation - though you may wish to contact a blood donation organisation for more specific information on how they handle &amp; categorise the blood.

But using just RhD and ABO gives 8 combinations, positive and negative of A, B, AB, and O. You can find out more about the blood groups, blood donation, and the characteristics of blood groups here. 

The subgroups you allude to are due to differences in the number of the antigens on the surface of the blood cell, for example the A1 group have ~1,000,000 A antigens per cell whereas A2 variants have ~250,000. The A group has ~20 subgroups, the vast majority of people are A1 (~80%) or A2 (~20%), and the other groups make up less than 1% of the population.


  These two subgroups are interchangeable as far as transfusion is concerned, but complications can sometimes arise in rare cases when typing the blood.