Scientists Unveil New Blood Group System Solving 50-Year Mystery

The discovery of the MAL blood group and its genetic basis provides critical insights for treating rare blood disorders.

Researchers from NHS Blood and Transplant and the University of Bristol identified the AnWj antigen as part of the new MAL blood group system.
The AnWj antigen, discovered in 1972, had an unknown genetic background until now, making this a significant breakthrough.
AnWj-negative individuals, who are extremely rare, can face life-threatening transfusion reactions if given AnWj-positive blood.
The team used whole exome sequencing to reveal that homozygous deletions in the MAL gene are responsible for the AnWj-negative phenotype.
This discovery will enable the development of new genotyping tests to identify AnWj-negative patients and donors, improving transfusion safety.