The golden blood type or Rh null blood group contains no Rh antigens
The golden blood type or Rh null blood group contains no Rh antigens (proteins) on the red blood cell (RBC). This is the rarest blood group in the world, with less than 50 individuals having this blood group. It was first seen in Aboriginal Australians. The worry with the golden blood group is that the donations of Rh null are incredibly scarce and difficult to obtain. An Rh null person has to rely on the cooperation of a small network of regular Rh null donors around the world if they need the blood. Throughout the world, there are only nine active donors for this blood group. This makes it the world’s most precious blood type, hence the name golden blood.
Our red blood cells have proteins called antigens on their surface. Depending on the antigen present, we have either A, B, O, or AB blood type. The ABO system has a further distinction as Rh-positive or Rh-negative depending on the presence or absence of the ‘Rh-D’ factor on the cells.
In the golden blood group, the individual lacks all the Rh antigens whereas a person with Rh-negative blood group lacks only RhD antigen.
Why do some people have golden blood type?
The golden blood group seems to be a result of genetic mutation (spontaneous change in the gene). It is commonly seen with mutations in the RHAG gene, which codes the Rh-associated glycoprotein. This protein is required for directing the Rh antigens to the RBC membrane.
RHAG mutation is often associated with a disease called hereditary stomatocytosis. These individuals can have long-term, mild, hemolytic anemia and increased RBC breakdown. The Rh-null phenotype can also be seen in the case of certain anemias a person may be born with.
The following conditions may put you at a higher risk of golden blood group:
- Consanguineous marriage (marriage between cousins, brother-sister, or anybody who is a near or distant relative)
- Autosomal genes (abnormal genes, which have disease traits, passed down through families)
- Changes or complete deletion of certain genes, which are RHD and RHCE or RHAG
What are the complications of golden blood type?
The people with Rh null or golden blood type usually may have
- Mild to moderate hemolytic anemia since birth: This leads to faster destruction of RBCs. This may cause low hemoglobin levels causing paleness and weariness. This occurs due to structural defects in RBCs like
- Mouth-like or slit-like shape
- Less elastic structure of red cells
- Abnormal red cell covering
- Increased fragility due to the lack of Rh antigen
- Altered blood cell volume
- Blood transfusion challenges: These people might face challenges during a blood transfusion. If this person’s blood is exposed to Rh antigens (proteins on the surface of RBC) from other’s blood, they readily form corresponding autoantibodies and there may be severe transfusion reaction. Therefore, for these types of patients, hospitals need to have special protocols set and quick response management.
- Rh incompatibility during pregnancy: If the mother has Rh null and the baby has Rh-positive blood type and if the mother’s blood gets sensitized by the baby’s positive blood. Then mother’s blood may produce protective proteins called antibodies that could target future pregnancies or lead to abortion or miscarriage.
- Hemolytic crisis: Several studies have found that any infection or sepsis in such individuals has precipitated massive hemolysis, subsequent kidney failure, and other complications.
Can golden blood type be donated?
Yes, golden blood can be donated. Because of the absence of antigens on RBCs, a person with Rh null blood is considered to be a universal donor, and this blood can be donated to anyone with rare blood types within the Rh systems.
This blood is excellent for transfusion because it lacks common antigens, and it can be accepted by anyone who needs a transfusion without the risk of a blood transfusion reaction. However, due to its rarity, it gets extremely difficult to find this type.
Conversely, Rh null is usually not so good for the people who have it. If they ever require a blood transfusion, receiving any blood that does have the Rh antigen may inevitably cause a transfusion reaction.