Discovered in 2025, the Gwada Negative blood type is known to exist in only one woman, but rare blood types are very useful for research and treatments.
Blood type O Negative is unusual, but somewhat common, with cases in 7 percent of the U.S. population. But the following blood types are super rare.
Rhnull (Golden Blood): Only 50 known cases of this blood are known to exist. It is useful because it lacks all 61 RH antigens. That means it is a universal donor for people with nearly any blood type. Critical for scientific research.
Bombay Phenotype (hh Blood Type): About 179 known cases exist in India, where blood banks prioritize identifying cases and storing it. Since it lacks the H antigen, this blood can be donated to those with A, B, AB, and O blood types, reducing immune reactions. But Bombay cases can only receive Bombay blood.
Ro Kell Negative: In high demand, this type is found in 2 percent of blood donors, especially in African American populations. Critical for treatment of sickle cell disease. Highly sought after.
Duffy-Negative and U Negative: Rare but more common in Africa and Middle Eastern populations, it exists in 1 percent of non-African populations. Duffy-Negative offers natural resistance to some malaria strains. Critical for sickle cell treatment.
