| A | B |
|---|
| O negative | universal donor |
| AB positive | universal recipient |
| AB negative | has only A and B proteins |
| O positive | most common types of blood in US |
| A positive | can give to AB positive and get blood from A negative |
| A negative | can give blood to A positive or AB negative but not to B negative |
| B positive | has B and Rh proteins |
| B negative | can receive blood from B negative but not A negative or B positive |
| rh / rh | genotype for negative blood |
| Rh / Rh | homozygous dominant |
| Rh / rh | positive blood with one parent having negative blood |
