ABO Blood Group Flashcards
what was the first blood group to be ID
ABO
t or F: the ABO blood group has naturally occurring ab
T
where do expected abs come from
Environmental factors
what kind of immunoglobulin are anti a anti b abs
IgMs
what do anti A and Anti b activate
complement
what kind of rejection occurs if a pt is transfused with ABO incompatible blood
acute humeral rejection
how is the ABO blood group inherited
mendelian genetics
what kind of alleles are the ABO gene
autosomal co-dominant
what chromosome has the ABO locus
chromosome 9
if both parents are type A can they produce a type O baby
yes because mom and dad could each have 1 O gene and the baby could get both
what is the heterozygous form of type A blood
AO
what is the homozygous of type A blood
AA
what is the genotype of type O blood
OO
what is the genotype of type AB blood
AB
what ag do type O pt have
H
what kind of structure do ags have
carbohydrate
what genes have products that affect the expression of ags
ABO, Hh, and Sese
what kind of sugar chain is the H precursor substance
4 sugar chain
what sugar is added to the H precursor substance
L-fucose
where is the H gene located
on type 2 chains beta 1 –> 4 linkage
H gene rxn with precursor substance + _____ = __ ag
fucose, H
what gene is required for the production of A or B ags
H gene
is the h gene amorph
yes
what adds sugars to the H ag to make A or B ags
glycosyltransferases
T or F: all H genes are converted into A or B ags
F
what blood groups have the most H ag (most to least)
O > A2 > B > A2B > A1 >A1B
what is the name for this genotype hh
bombay
what RBC ag do Bombay pt have
none
what plasma ab do Bombay pt have
potent anti H, anti A, and anti B
what is the location of H (FUT 1) gene
chromosome 19
what is the location of Se (FUT 2) gene
chromosome 19
if a person has A or B ags in their body fluids what are they considered
secretors
T. or F: a secretor will have Ags in the CSF
F
what kind of body fluid have secreted free oligosaccharides (secretors)
milk and urine
is it more common to be a secretor or not
secretor
what ags do secreters secrete
A, B, or H
where are ABH glycolipids ags found
imbedded in cell mmb
where are ABH glycoproteins ag found
secreted into exocrine fluid
what is the basic backbone of RBC ag
glycolipids
what is the precursor chain of RBC ags
type 2
what is the linkage of RBC ags
beta 1–>4
what is the L-fucosyltransferase of RBC ags
FUT 1 by H gene
what is the basic backbone of ABO soluble substances
glycoproteins
what is the precursor chain of ABO soluble substances
type 1
what is the linkage of ABO soluble substances
beta 1 –> 3
what is the L- fucosyltransferase of ABO soluble substances
FUT. 2 by. Se gene
what blood type do Bombay pt type as
O
if a Bombay pt needs a transfusion what kind of blood is given
bombay donor blood
The major immunoglobulin class(es) of anti-B in a group A individual is (are):
IgM
What are the possible ABO phenotypes of the offspring from the mating of a group A to a group B individual?
O, A, B, AB
The immunodominant sugar responsible for blood group A specificity is:
N -acetylD -galactosamine.
What ABH substance(s) would be found in the saliva of a group B secretor?
H and B
anti a = 4+, anti B = 4+, anti A1 = neg, A1 cells= 2+, B cells = neg. The reactions above may be seen in a patient who is:
A 2 B with anti-A1
Which of the following ABO blood groups contains the least amount of H substance?
A 1 B
You are working on a specimen in the laboratory that you believe to be a Bombay phenotype. Which of the following reactions would you expect to see?
Patient’s cells + Ulex europaeus = no agglutination
An example of a technical error that can result in an ABO discrepancy is:
Cell suspension that is too heavy.
anti a = 4+, anti B = neg, A1 cells= 2+, B cells = 4+, O cells= 2+, autocontrol= neg. These results are most likely due to
Non-ABO alloantibody.
what is the most blood subgroup
A
what reagent does not always react well with anti a reagent
A2 cells
what type of A subgroup is more common
A1
what blood subgroup has anti A1 in sera
A2B (more common) and A2
what is the phenotype of anti a= + and anti A1 = +
A1
what is the phenotype of anti a= + and anti A1 = neg
A2
does A1 or A2 produce more enzyme that converts H ag
A1
what are the possible genotypes of A1 phenotype
A1A2
what are the possible genotypes of A2 phenotype
A2A2 or A2O
what subgroup do group A infants appear as
A2
true or f: anti B1 exists
F
what does it mean to be cis AB
a and b gene are on the same chromosome
what are the parents of a cis AB child
AB and O
what needs to be tested for ABO blood typing
RBC and plasma/serum
what is detected for the forward type ABO typing
A or B ags on RBC mmb
where do you get Anti a and anti B from
type O pt
in a forward type rxn. if it is not 4+ what does this mean
subgroup present
what does reverse type testing detect
abs to A, B, AB, or H
t or f: reverse typing should not be preformed on children less than 6 months
T
what kind of immunoglobulin are ABO abs
IgM
do ABO abs cross the placenta barrier
no
what blood group has the highest titers for anti a
type O
at what age are ab levels fully developed
5 to 10 yrs
a what age do abo titers decrease
greater than 65
