She's the Only Known Person on Earth With This Blood Type

A 68-year-old woman from Guadeloupe has been identified as the sole person on Earth known to have a newly discovered blood type—one so rare that she is only compatible with herself. Scientists will next search to see if anyone else is part of the "Gwada negative" blood group—with Gwada being the colloquial name for her islands. The discovery, announced by scientists with the French Blood Establishment (EFS), marks the 48th recognized blood group system, reports Live Science (the ABO and Rh systems are the best known).

The AFP reports the woman's unusual blood was first noticed in 2011 during routine pre-surgical tests in Paris, but technology at that time couldn't determine her blood type or identify any matches. Her case remained unresolved until 2019, when researchers began what would be the sequencing of her entire genome, which turned up a mutation in the PIGZ gene that affects how certain proteins connect to red blood cells. Researchers plan to look for others with the Gwada negative blood type, starting in Guadeloupe, due to the genetic nature of blood groups. The EFS notes that of the 17 new blood group systems discovered since 2012, its research teams have played a role in finding 10 of them.