Biologist Bryan Ballif, Langereis & Junior blood type proteins

You probably know your blood type: A, B, AB or O. You may even know if you’re Rhesus positive or negative. But how about I tell you that in addition to those 2 systems (ABO and Rhesus), one could have as far as 28 other types in his blood? Intriguing, isn’t it?

28 in fact, until a week ago. The number has now grown to 30 with the discovery of 2 new blood types, raising the total, alongside the classics we know to 32 blood types discovered so far.

MNS, Lewis, Duffy, Kidd, Kell are the most known out of these systems. An A+ Duffy+ for instance, will face more restrictions if the donor wants to give blood and in this case the recipient must meet different criteria to be able to receive such blood, and not reject it nor have complications.

Those annex blood types are found mainly in some ethnic populations, or their genes could be transmitted throughout your family, and you may have some of them without even knowing!

Introducing Langereis and Junior
Langereis and Junior were discovered by a biologist called Bryan Ballif at the University of Vermont.

Biologist Bryan Ballif, who made the discovery.

The knowledge of you having these blood types could be “a matter of life and death“, he says in an interview conducted with Nature Genetics in the magazine’s February 2012 Issue.

While blood transfusion problems due to Langereis and Junior blood types are rare worldwide, several ethnic populations are at risk, Ballif notes. “More than 50,000 Japanese are thought to be Junior negative and may encounter blood transfusion problems or mother-fetus incompatibility,” he writes.

In addition to certain Japanese populations, European Gypsies are also at higher risk for not carrying the Langereis and Junior blood type proteins.

“There are people in the United States who have these challenges too,” he says, “but it’s more rare.”

History of the 2 blood types’ discovery

Although the antigens for the Junior and Langereis (or Lan) blood types were identified decades ago in pregnant women having difficulties carrying babies with incompatible blood types, the genetic basis of these antigens has been unknown until now.

Therefore, “very few people learn if they are Langereis or Junior positive or negative,” Ballif says.

Blood types are coded by proteins found on the surface of red blood cells, the ones we give when donating blood. Ballif identified the two molecules for the Langereis and Junior types as specialized transport proteins named ABCB6 and ABCG2.

The last new blood group proteins to be discovered were nearly a decade ago, Ballif says, “so it’s pretty remarkable to have two identified this year.“

“Now that we know these proteins, it will become a routine test,” he says.

A treatment for some cancers? An organ transplant savior?

On another note, this science may be especially important to organ transplant patients. “As we get better and better at transplants, we do everything we can to make a good match,” Ballif says. But sometimes a tissue or organ transplant, that looked like a good match, doesn’t work — and the donated tissue is rejected, which can lead to many problems or death.

“We don’t always know why there is rejection,” Ballif says, “but it may have to do with these proteins.”

What is even more fascinating is that those newly identified proteins are also associated with anticancer drug resistance, so the findings may also have implications for improved treatment of breast and other cancers.

This discovery would help a lot people with such blood types, and “will leave them better prepared to have blood ready when blood transfusions or other tissue donations are required,” he notes.

Many more to be discovered

Ballif and his international colleagues are not done with their search. “We’re following up on more unknown blood types,” he says. “There are probably on the order of 10 to 15 more of these unknown blood type systems — where we know there is a problem but we don’t know what the protein is that is causing the problem.”

Although these other blood systems are very rare, “if you’re that one individual, and you need a transfusion,” Ballif says, “there’s nothing more important for you to know.”

UNIVERSITY of VERMONT