Scientists Identify New Blood Group System, Resolving 50-Year Mystery
Researchers have discovered the MAL blood group system, elucidating the genetic basis of the AnWj antigen absence observed since 1972.
In 1972, a routine blood test on a pregnant woman revealed the absence of the AnWj antigen, a molecule present on the surface of red blood cells in over 99.9% of individuals. This anomaly puzzled scientists for decades. In 2024, researchers from NHS Blood and Transplant (NHSBT) and the University of Bristol identified the genetic basis of this phenomenon, leading to the classification of a new blood group system named MAL.
The team discovered that individuals lacking the AnWj antigen possess mutations in both copies of the MAL gene, resulting in the absence of the Mal protein on red blood cells. This protein is essential for cellular stability and transport.
Louise Tilley, a senior research scientist at NHSBT, emphasized the significance of this discovery, stating, "It represents a huge achievement, and the culmination of a long team effort, to finally establish this new blood group system and be able to offer the best care to rare, but important, patients."
Understanding the MAL blood group system enhances the ability to identify and treat patients with this rare blood type, reducing the risk of transfusion reactions and improving patient care.