Some interesting information on blood types:

Blood Type O Rh positive--Pitta or Pitta-Kapha dual--holds true 65% of the time.
Type O Rh negative--Pitta predominant--true 70% of the time.
Type A--Vata Predominant--true 80% of the time.
Type B--Kapha Predominant--true 80% of the time.
Type AB--Vata-Kapha dual--true 65% of the time.
Vata is Ether (or Space)/Air elements
Pitta is Fire/Water
Kapha is Water/Earth

Source: Textbook of Ayurveda: Fundamental Principles by Vasant Lad.


Other relevant information:

Type A should receive from type A. Type B from type B.
Type O is considered the universal donor. Type AB the universal recipient.


And one of Rumi's shorter poems:

The wine we really drink is our own blood.
Our bodies ferment in these barrels.
We give everything for a glass of this.
We give our minds for a sip.