Researchers Identify MAL Blood Group, Resolving 50-Year AnWj Antigen Mystery
Scientists have discovered the MAL blood group system, elucidating the genetic basis of the AnWj antigen first identified in 1972.
In 2024, researchers from NHS Blood and Transplant (NHSBT) and the University of Bristol identified a new blood group system named MAL, resolving a 50-year-old mystery surrounding the AnWj antigen discovered in 1972. The study, published in the journal Blood, revealed that the AnWj antigen is carried on the Mal protein, encoded by the MAL gene. Over 99.9% of individuals possess this antigen due to the presence of full-length Mal protein on their red blood cells. However, those with homozygous deletions in the MAL gene lack the AnWj antigen, resulting in the rare AnWj-negative phenotype. This discovery enables the development of genotyping tests to identify individuals with this rare blood type, thereby reducing the risk of transfusion-related complications. Senior research scientist Louise Tilley from NHSBT emphasized the significance of this finding, noting that it allows for better care of rare patients lacking this blood group.