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There is a LOT more to blood! There are a total of 36 different blood group systems, with the most important being the ABO group that everyone knows gives you y
by bearmode 4y ago
There is a LOT more to blood! There are a total of 36 different blood group systems, with the most important being the ABO group that everyone knows gives you your A, B, O, or AB blood, and the (RHD gene of the) Rh group that gives you the + or - part of it.
When given a single transfusion, a patient can usually be given blood based on the ABO and +/- part of the Rh groups alone, but there's more to the Rh system than most people know.
As well as the RHD gene, there's also the RHCE gene. The RHD gene can either be present (D, gives you positive blood) or not present (d, gives you negative blood), but the RHCE gene can give you one of four variations of the C, c, E and e antigens. When the two genes combine, you can have any of the following combinations: Dce, DCe, DcE, DCE, dce, dCe, dcE, dCE (which were given simplified names: Ro, R1, R2, Rz, r, r', r", ry respectively).
When patients have to be given regular blood transfusions, especially on a long-term basis, the blood they receive has to be more precisely matched. That's often why there's always a huge push for black donors - because many black people suffer from sickle cell anaemia, for which the treatment is regular blood transfusions, they need blood that better matches their own.
- junon 4y agoThis is fascinating, thanks for sharing. Are there more groups than just A, B and O?
- bearmode 4y agoThe ABO group system relates to a gene called ABO, which gives you your A, B, AB, or O type. I'm not aware of any other blood types in that system (though I'm just an eager blood donor, not a haematologist). There are lots of other systems though that add up to make your blood what it is. There's the Rhesus (Rh) system I mentioned before, but the main ones also include the MNS system, the P system, the Lutheran system, the Kell system, the Lewis system, the Duffy system, and the Kidd system. As far as I know, Kell is the third most immunogenic system after ABO and Rhesus.
- roywiggins 4y agoThey apparently discover new sets of blood groups every few years, there are some vanishingly rare types. https://www.wired.com/story/new-blood-types/ https://www.wired.com/story/new-blood-types/
- echelon 4y agoIt's so complicated. Just one more example: infants express a different set of hemes that have higher oxygen binding affinity. The switch from fetal to adult heme is being investigated as a potential cause of SIDS.
- _tom_ 4y agoAnother comment says this is based on the donor. So, if you can self donate, or find one matching donor, you should be able to get a match every time. Obviously, custom tailored stuff is likely to take longer to develop, but it seems feasible.