In a historic medical breakthrough, researchers in Bengaluru and the UK have discovered a never-before-seen blood group antigen—named CRIB—in a 38-year-old woman from Kolar district, Karnataka. This marks the first-ever identification of the CRIB antigen globally.
The Discovery
Though initially typed as O Rh-positive, her blood proved incompatible with all available O-positive units—and even unmatched among 20 family members—triggering advanced testing. The case was referred to the Rotary Bangalore TTK Blood Centre and later confirmed by the International Blood Group Reference Laboratory (IBGRL) in the UK after 10 months of serological and genetic analysis
Naming & Classification
The antigen was officially named CRIB—a nod to its classification under the Cromer (CR) blood group system, and its origin: CR‑India‑Bangalore. It falls within the INRA (Indian Rare Antigen) system recognized by the ISBT.
Why CRIB Is So Rare
Only one individual is known to carry CRIB, making it among the world’s rarest blood types. Individuals with CRIB lack a high-prevalence antigen found in almost everyone else. This results in severe transfusion incompatibility—only CRIB-negative blood can be safely transfused, which is nearly impossible to source.The Economic Times
Medical Relevance
CRIB’s identification could change how doctors approach Hemolytic Disease of the Fetus and Newborn (HDFN), enabling preventative care during pregnancy for at-risk cases. In emergencies requiring transfusions, autologous storage of the patient’s own blood may be the only viable option.
Actions Taken
Following the discovery, the Rotary Bangalore TTK Blood Centre, in collaboration with the Karnataka State Blood Transfusion Council and ICMR, launched a Rare Donor Registry to improve identification and support for ultra-rare blood types like CRIB.
Global Significance
CRIB’s discovery underscores India’s leading role in immunohematology and global blood research. It highlights the urgent need for wider donor screening networks and investment in rare-blood infrastructure. Experts predict this will prompt updates to global transfusion protocols, genetic testing, and critical care strategies worldwide.
Conclusion
The CRIB antigen represents a milestone in medical science—reshaping the understanding of rare blood groups and their impact on life-saving care. India’s collaboration with international research bodies signals a new era in transfusion medicine and rare blood management.
