Scientists at the French Blood Center (EFS) announced the discovery of a rare blood type, named "Gwada-negative," in June 2025.
This blood type was found in only one woman from Guadeloupe, making it the only known case in the world. The discovery was made after an unusual antibody was detected in the woman's blood during routine pre-surgery tests in 2011.
Using large-scale DNA sequencing in 2019, scientists identified a specific genetic mutation responsible for this unique blood type. The International Society of Blood Transfusion (ISBT) recognized "Gwada-negative" as the 48th confirmed blood group system in the world in Milan in June 2025.
The woman inherited the mutation from both parents, making it a unique case. This discovery expands our understanding of blood group systems and could improve the safety of blood transfusions, especially when a very specific blood type is needed.