After nearly 50 years of research, scientists have made a groundbreaking discovery: a new blood group system called MAL, which helps explain the mysterious AnWj antigen. This latest finding results from dedicated work by researchers from NHS Blood and Transplant (NHSBT), the International Blood Group Reference Laboratory (IBGRL), and the University of Bristol.
The AnWj antigen was first identified in 1972. However, scientists didn’t know the genetic background behind it. This left a significant gap in our understanding of blood groups, and for decades, researchers puzzled over its origin. Despite knowing that most people carry this antigen, a tiny percentage of individuals did not, but the reason why remained unclear.
The researchers discovered that the AnWj antigen is carried by a protein called Mal, produced by the MAL gene. In more than 99.9% of people, the MAL gene is intact, and they are AnWj-positive, meaning they have the antigen on their red blood cells. But in very rare cases, some individuals lack the MAL gene due to a genetic deletion, making them AnWj-negative. These individuals form part of the new MAL blood group system, the 47th blood group to be recognized.
You’ve probably heard of the ABO and Rh blood group systems, which are crucial for safe blood transfusions. Within each system, there are many antigens—tiny markers on RBCs that help determine compatibility. The newly discovered MAL blood group is another important system that adds to this complexity.
For people who are AnWj-negative, receiving blood that is AnWj-positive could cause dangerous transfusion reactions. These reactions happen because the body sees the foreign antigen as a threat, leading to complications. Now that we know the genetic background of AnWj, doctors can develop genotyping tests to identify these rare individuals and ensure they receive safe, compatible blood during transfusions.
This remarkable discovery didn’t happen overnight. It was the result of years of teamwork, using cutting-edge tools like whole exome sequencing (which analyzes the protein-coding parts of DNA) to unlock the genetic mystery. The breakthrough came when the team identified a handful of people who were AnWj-negative, including a family from the Arab-Israeli community.
The discovery of the MAL blood group opens up new doors for the future of transfusion medicine and highlights the power of genetic research to improve patient care.
The future looks bright for MAL blood group research. With this discovery, scientists can now create new tests to identify rare AnWj-negative individuals more easily. This will help healthcare providers give better care to patients who need specialized blood transfusions.
This discovery is not just a scientific win—it’s a victory for patients around the world who will benefit from safer blood transfusions and personalized care.
Thanks for reading this blog!
