New Blood Groups Have Been Found by Scientists The ‘Er’ grouping could aid medical professionals in locating and treating some uncommon cases of blood incompatibility, such as that which occurs between expectant mothers and foetuses.
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New Blood Groups
The unborn child was in difficulty. A UK hospital’s doctors chose to conduct an emergency C-section many weeks before the baby was due since they knew there was something wrong with the fetus’s blood. However, despite this and more blood transfusions, the infant experienced a brain bleed that had grave implications. It tragically died.
The cause of the haemorrhage was unclear. However, there was a hint in the mother’s blood, where medical professionals had found some odd antibodies. A sample of the mother’s blood came in a lab in Bristol run by experts who study blood groups some time later, when the medical professionals were attempting to learn more about them.
They made an unexpected finding: The woman’s blood type was ultrarare, which would have rendered her child’s blood incompatible with her own. It’s likely that this caused her immune system to manufacture antibodies that were harmful to her unborn child and ultimately caused its death. These antibodies may have been produced in response to the blood of her unborn child. Although it may seem unlikely that such a thing could occur, it actually happened rather frequently many years ago, before doctors had a better understanding of blood kinds.
Scientists were able to determine exactly what made the mother’s blood distinctive by examining it along with several other blood samples. In the process, they confirmed a new system of blood grouping—the “Er” system, the 44th to be defined.
The four main blood types—A, B, O, and AB—are presumably already familiar to you. However, this is not the sole system for categorising blood. Based on variations in the sugars or proteins that cover the surface of red blood cells and are referred to as antigens, there are numerous ways to classify red blood cells. Your blood can be categorised using any of the grouping methods because they operate simultaneously; for example, type O in the ABO system, positive (rather than negative) under the Rhesus system, etc.
Because antigens differ, if someone obtains incompatible blood from a donor, their immune system can mistake the antigens for foreign substances and mount an attack. Because of the potential for serious harm, donated blood for transfusions must match the recipient’s blood type.
Over the past ten years, researchers have reported an average of one new blood classification system per year. These more recent methods frequently use blood types that are astonishingly uncommon, yet for individuals affected, simply knowing that they do could be lifesaving. This is the account of how researchers solved the puzzle of the most recent blood system and why it is significant.
Researchers first discovered an uncommon antibody in a blood sample in 1982, providing evidence that an unidentified blood type existed. The researchers recognised that the antibody was a sign pointing toward an unidentified molecule or structure that caused the person’s immune system to produce it, but they couldn’t go much further than that at the time.
More cases of these unique antibodies appeared in the years that followed, but only occasionally. These individuals typically came to light as a result of blood tests that revealed the odd and uncommon antibodies. Nicole Thornton and her coworkers at NHS Blood and Transplant in the UK ultimately made the decision to investigate the potential causes of the antibodies. We work on uncommon cases, she claims. The process begins with a patient who has an issue that we are attempting to fix.
In the years that followed, there were a few more instances of these particular antibodies, but they were rare. Blood testing that identified the peculiar and unusual antibodies often led to the discovery of these people. In the end, Nicole Thornton and her colleagues at NHS Blood and Transplant in the UK decided to look into possible causes of the antibodies. She says that we handle rare cases. The patient with the problem that we are trying to solve starts the process.
It turns out that a specific protein present on the surface of red blood cells is connected to the novel 44th grouping system, described in the journal Blood.
Thornton initially suspected this protein, named Piezo1, was involved after comparing the genomes of study participants. She and her coworkers discovered that individuals with various Er blood types have different variations in the gene that codes for this protein. A small percentage of people have different amino acids, or protein building blocks, in their Piezo1 protein as a result of those genetic variations. The immune systems of their bodies perceive blood cells with the more frequent Piezo1 protein as foreign.
The scientists then examined whether antibodies responded to lab cultures that either included mutant copies of the Piezo1 protein or did not, which was produced through gene editing. This allowed them to verify that Piezo1 variation was, in fact, the cause of blood incompatibility in the individuals whose samples they were examining. According to coauthor Ash Toye, professor of cell biology at the University of Bristol, “that was something you couldn’t have done a few years ago.”
There are a total of five Er antigens, or five possible iterations of Piezo1 on the surface of red blood cells. Thornton and her colleagues discovered two novel antigens, one of which was discovered in the blood of the pregnant woman in the UK who miscarried.
The International Society of Blood Transfusion meeting later this year is likely to formally ratify the study’s findings as designating a new blood group system. The amount of labour necessary to make the discovery was “huge,” according to Neil Avent, an honorary professor in the University of Plymouth’s blood diagnostics section who was not involved in the research. It also highlighted the complexity of this unusual blood, such as the fact that it is linked to numerous genetic abnormalities.
A different team of researchers from across the Atlantic had also been working to decipher the mysteries of the new Er blood group, but they were defeated by the British team. According to Connie Westhoff of the New York Blood Center, who participated in the US research, “that happens in our profession.” We are frequently aware of the fact that we are working in multiple laboratories to locate the answer.
She claims that further blood samples she and her coworkers have come from people who appear to have the uncommon blood group Er. She adds that there may yet be further genetic changes linked to this unusual blood that need to be discovered.
“Learning about a new blood group system is like learning about a new planet. It broadens the scope of our experience, adds Saint Louis University School of Medicine’s Daniela Hermelin, who was not involved in the study. She says it increases our understanding of the potential effects of blood incompatibility on expectant moms and their unborn children. And now that cases of blood incompatibility may be linked to the Er blood group, it improves the likelihood that clinicians will be able to accurately identify and treat such a condition, such as by providing the infant a blood transfusion while still in the womb.
Additionally, it will be possible to detect and recognise patients who have this problematic blood. For instance, before receiving a transfusion, a patient may visit the hospital for a preliminary blood test that identifies the existence of some uncommon antibodies. It’s possible that when the blood is analysed by the doctors, it will be discovered that they have the uncommon Er blood detailed in the report. According to Thornton, “We have our testing setup to be able to do that.” Then, she continues, it could be necessary to transfuse that person with rare blood. Red blood cells that could be provided to these individuals for transfusion in the future may be grown in a laboratory.
According to Avent, it’s quite improbable that you would be incompatible with someone else’s blood because to Er antigens. If you do, though, you should be aware of it.
