Golden blood (Rh-null)
Red cells with no Rh antigens at all. Found in roughly 50 people ever reported, it’s the rarest blood type known.
What makes it “golden”
The Rh system is huge: more than 50 antigens, of which D is the one that decides “positive” or “negative”. Rh-null red cells carry none of them. The first case was described in 1961 in an Aboriginal Australian woman, and only a few dozen people have been found since.
The nickname comes from its value. Because it lacks every Rh antigen, Rh-null blood can help patients with other rare Rh types who have made antibodies against common Rh antigens. But donors are so few that units are frozen and shipped internationally through the rare donor network coordinated by the International Blood Group Reference Laboratory in Bristol, UK.
How it happens
- Amorph type: inheriting two non-working copies of the RHD/RHCE genes.
- Regulator type: inheriting two faulty copies of the RHAG gene, whose protein is needed to carry Rh antigens to the cell surface.
Both are recessive, so parents are usually unaffected carriers, and many cases occur in families where the parents are related.
Living with Rh-null
Rh-null cells are a slightly different shape and can break down faster, so some people have mild haemolytic anaemia. The bigger practical risk is transfusion: they can only safely receive Rh-null blood, so many are encouraged to bank their own blood in advance.
Rh-null sits alongside the Bombay blood type as one of the rarest blood groups. Among the everyday eight, AB negative is the rarest.
Frequently asked questions
What is golden blood?
Golden blood is the nickname for Rh-null, a blood type whose red cells carry none of the Rh system’s antigens. It is called golden because it is extraordinarily rare and precious for transfusion.
How many people have golden blood?
Only around 50 people have been reported worldwide since it was first described in 1961, with fewer than ten active donors known at any time.
Who can receive golden blood?
Rh-null red cells can in principle be given to people with rare Rh types who lack high-frequency Rh antigens. Rh-null people themselves can generally only receive Rh-null blood.
Is Rh-null the same as Rh negative?
No. Rh-negative cells lack only the D antigen. Rh-null cells lack all Rh antigens (D, C, c, E, e and more than 50 others).