What is the Rarest Blood Group?

The Rarest Blood Group: Rh Null's Importance in Transfusions

The rarest blood group is Rh null. People who have Rh null blood group do not have Rh antigens on their red blood cells. Experts categorise blood groups according to the presence or absence of a protein called antigens, which is attached to the red blood cells. There are eight blood groups available, but out of these eight groups, the AB- group is the least common, but Rh null is the rarest.

What Makes Rh Null Blood Rare?

The definition of a rare blood group is when the group is only available in 1 in 1000 people. Researchers found that the Rh null group is available to only 1 in 6 million people. Because of its rarity, people refer to Rh null as the golden blood type.

Having a rare blood type can make it challenging or even impossible to receive a blood transfusion or organ transplant from other people. Incompatible blood during pregnancy can cause complications for women with rare blood types.

Researchers categorise most blood types into one of four groups based on the presence of A or B antigens. For instance, those with A antigens have type A blood, while people with B antigens have type B. Individuals with both A and B antigens have type AB, while those who do not have antigens on their red blood cells are classified as type O.

Along with their blood group type, some people may also have the Rh factor in their red blood cells. Those who do not have the Rh factor are classified as having Rh-, whereas those who have the Rh factor are classified as Rh+. For instance, a health professional would consider an individual with AB blood and the Rh factor to have AB+.

Some people, such as those with Rh null, may lack one or more common antigens. Currently, researchers have recognised 47 additional blood groups and identified over 600 antigens.

Who Possesses the Rh null or Golden Blood Type?

The Rh null group is a result of a genetic mutation. This group is generally found with the mutation of the RHAG gene. This mutation is associated with hereditary stomatocytosis disease. These people may experience chronic, mild haemolytic anaemia and increased breakdown of red blood cells. The Rh-null phenotype can also be found in people who were born with anaemia.

Ethnicity of the Rare Blood Group

Blood groups can be varied across populations and regions. Researchers once tried to categorise people into their ethnicity based on their blood groups. However, they found out that blood groups cannot be categorised into race or ethnicity. Nevertheless, the distribution of ABO groups among Caucasian, African American, Asian, and Latino Americans in the U.S. does differ.

O groups are the most common blood group across the globe. Almost 43% of people in the US have this blood group. An older study shows that around 63% of the world’s population

have this O type. Also, AB groups are the rarest among all the other groups in the US, which is around less than 5%. In addition to that, Rh+ group is more common than Rh- across the world.

What Makes Rh null so Valuable?

It is valuable due to its rarity. For instance, only 1 in 6 million people have this group. People with this type can safely donate to any other blood group without any risk of deadly transfusion reactions. Rh-null blood lacks all 61 possible Rh antigens on red blood cells, making it one of the rarest blood types in the world.

In fact, this unique absence makes Rh-null extremely valuable for transfusions, but it is also risky, as compatible donors are exceptionally few. However, people with Rh Null cannot receive blood from any other groups