Researchers encountered unusual reactions while examining a blood sample from a woman from the Guadeloupe district in France and discovered the world’s rarest blood type; they said that the woman’s blood plasma did not match any of the samples donated for testing, and this incompatibility even existed with samples from the woman’s siblings.
To find the cause of this woman’s blood incompatibility, they used an advanced technique called “whole exome sequencing” and succeeded in identifying a mutation in her PIGZ gene; this gene produces an enzyme that adds a specific sugar to a molecule in the cell membrane, the absence of which caused a change in the structure of the molecule on red blood cells and led to the creation of a new antigen.
The researchers’ study led to the identification of the 48th known blood type in the world, which is called “Gwada-negative” and is considered the rarest blood type in the world.
