HH group is the rarest blood group which is mostly seen in the Indian people. It is newly known as it is rare with the difference in composition to the other groups. Those who have the rare HH blood group may fall in difficulty as it can accept and donate to the same. So, for those who are found with this unique blood is in the rarest of all blood groups. Since it is not common finding out the donor to this group is always difficult.
Discovery of HH blood group
Until 1952, there were only A, B, O, and AB in the list and universal donor and acceptor. It was in this year that Dr. Y M Bhende was able to find out another blood phenotype which is known as the HH group. It is also recognized as Bombay Blood Group. The strange feature of HH is that the RBC does not have any of the ABO antigens.
It lacked the entire ABO phenotypes and at that time this new antigen was not known until further researches. After studies and researches it was discovered that the new antigens are able to donate red blood cells to the A antigens and also B antigens or any members of ABO blood groups.
Often HH is confused with the O group, so those patients who need belong to this group may face risks leading to the acute hemolytic transfusion reaction. To avoid any mistakes it is essential that the lab technician should be aware of this unique blood group. Tracing the difference between the donors is mostly predicted as O due to the common features and characteristics.
But as another new group is in the list, the lab tests should be done keeping in mind about the new donor HH blood group.
Facts about this Bombay blood
As it is a rare blood group often the complications may rise due to the lack of availibity or finding the features of the blood groups. So, it has become necessary that few facts of Bombay blood should be known to reduce risks.
The H antigen present in blood group O is not suitable for the those who have the anti H in circulation in the body. It may lead to the acute hemolytic transfusion reaction.
To understand and consider the HH blood group it is essential to know that it occurs for those individuals who inherited two recessive alleles of the H gene. It may or may not contain the A or B alleles, but if present, they can not express themselves.
From the name “Bombay Blood”, it is easy to understand the density of the blood groups is high in Mumbai areas. This rare group have the scarcity of blood even in the blood banks not only in India but all over the world.
To have this rare blood group a person should have the parents with dominance in H allele. It can be when both the parents have this blood group or recessive allele. As it can transmit the trait to their child. HH blood group is mostly within the Mumbai kars, and it is the reason that this blood group is rare in the world.