Guadeloupe: Discovery of a new blood type, called "Gwada negative"

This is quite a discovery. This Friday, a French woman of Guadeloupean origin was identified as the only known carrier of a new blood type, dubbed "Gwada negative" in reference to the patient's origins, said an official from the French Blood Establishment (EFS), confirming a report from France Inter.

As early as 2011, a "very specific" and "unknown" antibody was found in this patient, but the resources at the time did not allow for further research, explained Thierry Peyrard, a medical biologist pharmacist, head of the EFS for the quality and safety of blood products, and a researcher at Inserm. Scientists were able to "unravel the mystery" in 2019, thanks to "very high-throughput DNA sequencing," which highlighted a genetic "mutation," he added.

The discovery of this new group "was made official at the beginning of June in Milan by the International Society of Blood Transfusion (ISBT)," the EFS announced on social media.

Now in her sixties, the patient was "54 years old, living in Paris" and undergoing routine pre-surgery tests when the unknown antibody was detected, Peyrard recalled. "There is only one who is compatible with herself today in the world" for the moment, whereas for other rare blood types, a small group of people can be identified, such as siblings. This woman "is undoubtedly the only known case in the world."

But how is this possible? "This blood type is inherited from her father and mother," who each had "the mutated gene." Like their parents, the patient's siblings "carried only one allele" and therefore did not have this blood type, which is declared "with the two identical genes."

This discovery led to the naming of "a new family, called PIGZ, which has become the 48th blood group system in humans." The most well-known system, ABO, dates back to 1990. With his colleagues and thanks to the implementation (currently underway) of a special protocol, Mr. Peyrard hopes "to find other Gwada-negative people in Guadeloupe in particular, among blood donors."