India has reported its first case of EMM negative blood. What is unique about the type? Why does it not find a place in the existing blood groups?
IN SCHOOL DESK
One of the first things that schools ask when students enroll is their blood group. This crucial information is added to the identity card and student files so that, in case of a medical emergency, the information is available at hand. But can you imagine a scenario when a lab is unable to identify your blood group because it is extremely rare? That’s what happened when a 65-year-old man in Gujarat who had gone for cardiac treatment, tried to find out his blood group.
Even specialists were left puzzled as his blood sample did not seem to match others. The patient needed to know his blood group in order to have a compatible donor who could give him blood for a heart surgery. Only after a long ordeal ending with his blood sample being sent to the United States for testing, did the man find out that he had EMM negative blood. He is the first recorded case in India to have such a blood type and the tenth in the world. The blood group has been assigned with the symbol ISBT042.
What are blood types?
Blood is characterised into types to prevent adverse reactions during blood transfusions. In general, we know of the blood types A, B, O or AB. Further, these groups take on a negative or positive factor.
However, there are 42 different types of blood systems, including A, B, O, Rh, and Duffy. The names come from the ABO antigens, which are basically protein molecules that are found on our red blood cells. In most blood groups, EMM is present. But there are rare cases where EMM is negative.
In the case of the Gujarat man, even his children’s blood samples were not a perfect match and he could have had a reaction if their blood was given to him.
Why is the ISBT042 blood type so rare?
Understanding the Emm antigen has been a struggle even for scientists. But by studying those with the blood type and comparing their samples with those of relatives, scientists have found that a deletion in a gene could be responsible for the blood type. People with EMM negative blood group can’t donate blood to anyone or accept blood from anyone.
Picture Credit : Google
