There are different blood types: A, B, AB, and O, with each also being Rh-positive or Rh-negative. Knowing your blood type is important for safe blood transfusions and organ transplants. Type ...

Most people don’t spare a thought for their blood type unless they’re in need of a transfusion — but could yours hold secrets to your health? There are four main blood types: A, B, AB and O.

A routine medical test turned extraordinary for a woman from the Caribbean when doctors found something completely new in her blood. Nearly 15 years ago, while preparing for surgery in Paris, doctors ...

Step aside A, B, and O—there’s a new player in town. Scientists in France have just reported the discovery of a novel, rare blood type, only recorded in a single person to date. The French Blood ...

A person's blood type is determined by "the presence or absence of certain antigens – substances that can trigger an immune response if they are foreign to the body," according to American Red Cross.

Katie has a PhD in maths, specializing in the intersection of dynamical systems and number theory. She reports on topics from maths and history to society and animals. Katie has a PhD in maths, ...

In 2011, a woman from the French overseas region of Guadeloupe underwent routine tests before a surgery. Strikingly, doctors could not identify her blood group, which was so unique that they did not ...