A simple blood test, part of a patient’s pre-operative routine in Guadeloupe, revealed one of the rarest findings in modern medicine: the identification of a new blood group, christened Gwada, which now joins the 47 already recognised by science, bringing the total to 48 distinct blood-typing systems.
The discovery came when the patient’s plasma – she is the only person known in the world to have this group – showed a rejection reaction to all the samples tested, including those of her own siblings. The anomaly immediately caught the attention of the medical team, who turned to advanced genetic analysis to unravel the puzzle.
The examination revealed a mutation in the PIGZ gene, responsible for creating a new antigen – the element that defines blood compatibility between individuals. Thus Gwada was born, the name distinguishing between Gwada positive (presence of the antigen) and Gwada negative (absence of it). The patient in question belongs to the Gwada negative category.
Beyond its laboratory rarity, this mutation may have profound clinical implications. The woman has a mild intellectual disability and has already lost two children at birth. Doctors suspect that both conditions may be related to the genetic mutation that defines this new type of blood. However, a direct link between the altered gene and these clinical manifestations remains to be demonstrated.
The discovery also raises an urgent and practical question: it is not known what reaction could occur if the patient needed a blood transfusion that was not compatible with Gwada. The absence of donors with the same blood type puts her in a position of considerable clinical risk.
This singular case represents a scientific milestone – not only because it expands the limits of knowledge about blood groups, but because it challenges current transfusion compatibility norms. And, above all, it reminds us that there is still much to discover in the most vital of human tissues.
