Expert: Dana Krempels, Ph.D. - 2/6/2011

Question
QUESTION: sub : blood group and type information required

meDicine branch  : pathology

we have different blood groups viz.

a,b,ab and o.

and

blood group type rh + , rh -.

ab blood group classified as universal acceptor.
o blood group classified as universal donor.

a will only accept blood group a according to proper rh
b will accept only blood group b according to proper rh
ab can accept blood from any blood group
o will only accept blooD group a according to proper rh  


1. now a question which comes to my mind is there any significance
to the letters a,b,ab and o i.e expansion or meaning to these
letters

for example

wbc : white blood corpusels
rbc : red blood corpusels

our english alphabets characters are in the sequence
a,b,c,d,e ....z. i.e 26 characters.

2.another question

after a,b,ab and then the letter is o for the blood group why not
they have named c because after a,b the letter c comes in sequence.


3. another question

in future for human being/s species will there more blood group/s
i.e c, d, e .....similar to a,b.

4. another question

what about animals blood group ?

i.e cats,fishes,birds,frogs etc

do they have similar blood group a,b,ab, o or any other
blood group/s for matching blood Donor / acceptor ?


thanks & regards,
prashant s akerkar

ANSWER: Dear Prashant,

Type A and Type B blood are so named because of the type of immunoglobin inserted on the plasma membrane of the red blood cells.  Type A individuals have Immunoglobin A, and Type B individuals have Immunoglobin B.  (I am not sure why these were named "A" and "B", but it may be that they were discovered a very long time ago and were given simple names because of this.)  Type O individuals lack either type of immunoglobin (in this class) on their rbc's, so this explains the "o".  It means, essentially, a *lack* of the immunoglobins in the AB class.  

There are other immunoglobin groups in humans, including things like Rh (Rhesus) factors, and many others. But because the AB immunoglobins and Rh factors appear to be the most significant in eliciting immune responses, those are the ones of most concern in medicine.

Different species also have blood types, but they are different from the ABo and Rh factors found in humans.  Each species has its own immunoglobin classes, and transfusions within a species can be problematic for the same reasons they are in humans.

Hope that helps.

Dana

---------- FOLLOW-UP ----------

QUESTION: ms Dana

thank you.

require inputs for question 1,2

1. another question

in future for human being/s species will there more blood group/s
i.e c, d, e .....similar to a,b.

2. another question

what about animals blood group ?

i.e cats,fishes,birds,frogs etc

do they have similar blood group a,b,ab,o or any other
blood group/s for matching blood Donor / acceptor ?


thanks & regards,
prashant s akerkar

Answer
Dear Prashant,

In the future, the evolution of a new immunoglobin in the ABo group would require a mutation that changed one of those forms to a third form.  It could happen, hypothetically.  But it hasn't so far, so it could be that any significant change to the immunoglobin would be maladaptive.

Many animals also have blood groups, and each species has its own, specific immunoglobins.  I don't know what they are, off the top of my head.  But these are important in veterinary medicine, where transfusions are sometimes necessary.

Dana