An unknown blood type in the world has been identified in a woman in India

In a hospital in the state of Karnataka in southern India, a patient was found to have a previously unknown blood group antigen, which has not yet been found in anyone in the world. This was reported by the newspaper The New Indian Express.

The discovery was made in preparation for heart surgery of a 38-year-old resident of Kolar county. The O Rh+ blood group defined by her is the most common, but none of the available doses of the O-positive blood group suited her for a possible transfusion.

"Using advanced serological methods, our team found that her blood was "pan-reactive", incompatible with all test samples. Recognizing this as a possible case of a rare or unknown blood type, we collected blood samples from 20 family members of the patient to find a compatible one, but none of them came up," Ankit Mathur, a surgeon at the Kolara clinic, told the publication.

According to him, the operation was successful, without the need for blood transfusion.

The patient's blood samples were transferred to the International Reference Laboratory of Blood Groups (IBGRL) in Bristol (UK) and the Blood Center in Bangalore (administrative center of Karnataka). Scientists conducted molecular studies for ten months and confirmed the discovery of a previously unknown blood group antigen, which was officially named CRIB.

A number of immunologists consider the tradition of marriages between close relatives in the country to be a possible reason for the emergence of a blood type unknown to science in a resident of India.

The discovery was announced at the 35th Regional Congress of the International Society of Blood Transfusion (ISBT), held in Milan (Italy) in June 2025.

The Bangalore Blood Center, together with the Indian Medical Research Council in Mumbai, has created a Registry of voluntary Donors of Rare Blood groups, planning to include holders of the newly discovered CRIB group in it if they are discovered in the future.