A new genetic anomaly has been identified in just three individuals, revealing an extraordinarily rare blood type variation. The discovery, made by researchers at Mahidol University in Thailand after analyzing over 544,000 blood samples, highlights how much remains unknown about human blood compatibility.
The Complexity of Blood Typing
Human blood classification is based on the presence or absence of specific sugars and proteins on red blood cells, categorized into eight main types: A, B, AB, and O, with further distinctions made by the rhesus factor (+ or -). However, these categories only scratch the surface of true blood diversity.
The immune system relies on recognizing these markers as “self,” attacking any unfamiliar blood type during a transfusion. This is why matching blood types is critical, as mismatched transfusions can be fatal.
What is B(A)?
This latest discovery involves a mutation within the B(A) phenotype, a rare variation where type B blood exhibits slight A-like activity. This subtle difference can lead to discrepancies in standard blood typing tests, delaying patient care while doctors attempt to determine the correct blood type.
Researchers found four unique mutations in the ABO gene—the gene responsible for adding sugars to blood cells—that had never been reported before. This means the blood is technically type B, but behaves slightly like type A during testing.
Why This Matters
The frequency of this mutation is estimated at roughly one in 180,000 people, or 0.00055 percent of the population. While this is an exceptionally low occurrence, it underscores the possibility of other undiscovered blood variations lurking in the human genome.
This discovery also emphasizes the need for advanced genetic testing in cases where standard methods produce inconclusive results. In fact, genetic testing is becoming increasingly important, as another rare blood type – “Gwada-negative” – was discovered earlier this year in a patient from Guadeloupe.
Ongoing Research
Future studies will be needed to fully understand the impact of this mutated enzyme on blood function. However, this discovery serves as a reminder that our understanding of human biology is far from complete, and that even the most fundamental aspects of our bodies hold hidden complexities.
The identification of these rare blood types not only advances medical science but also reinforces the importance of continued research in genetics and immunology.
