Human blood already comes in a bewildering variety of types, but researchers have now identified a new one so rare that only three people on the planet are known to carry it. The finding exposes just ...

For those with kidney failure, a transplant is often the greatest promise of a healthier, longer life. Yet thousands wait years for a match that never comes. Incompatibility of blood type is one of ...

"Hearst Magazines and Yahoo may earn commission or revenue on some items through these links." Here’s what you’ll learn when you read this story: One of the biggest hurdles is availability, as there ...