Although, of course, the fact that only a select few have it is impressive. It is distinguished by the fact that it does not contain antigens, meaning that it is neither negative nor positive. Such ...

* Rh-null blood lacks all 61 Rh antigens, making it extremely rare and medically valuable * It can save lives as a universal donor within rare blood types * Rh-null individuals //can only receive ...

There’s more history in your blood types than you think, and it didn’t begin with humans. Here’s what we know about them, ...