Are "U Negative"?

Did you know that there is a blood type "U Negative"? It's true, BUT it is one the RAREST blood type in existence and only occurs in African Americans typically of South Africa or Caribbean descent.

Conversely, only Caucasians have the blood types Vel negative and Lan negative, . There are records of people having a blood type that exists only in a remote village or in one family.

A patient needing U negative blood, can only receive from another U negative, so the problem with availability is obvious. U negative can also be given to anybody who is B-positive (this is his main blood group), but is especially valuable for people who need regular blood transfusions, such as people with hemophilia or sickle cell anaemia.

This is because people who have regular blood transfusions, like me, can develop a serious reaction to certain parts of donor blood cells, called antigens. Many develop a reaction to one or more of the common antigens that most people have in their blood. A U-negative donor's blood does not have the common U antigen, and can be given without the risk of reaction.

When any blood is received at a donor center it has to be typed and if it is found to be rare, it will go through additional testing to determine how rare and if it's considered rare enough, rather than standard storage, it will be frozen for future use (unless needed immediately). Once it's frozen, it can be stored up to 10 years, however, once thawed it must be used within 24 hours.

U negative donors are so rare that they have even been flown to other countries in order to provide a donation to someone in immediate need.

So if you just learned about U Negative blood for the first time, don't worry, there will be lots of time to learn about the other blood groups too: JS(b), Cr(a), At(a), Rh17, Jk(b), Fy(a), Fy(b). Of those, Rh17 is the rarest and most are found amongst the African American community.

And don't worry, if you didn't know these rare types existed, I didn't either until yesterday and a behind-the-scenes tour of a blood donor center!