Deck 8: Blood Group Terminology and Common Blood Groups

Question 1

Why is anti-Le^bL the antibody of choice when phenotyping red blood cells?

A) It reacts best with O and A₂ cells.
B) It is dependent on the ABH antigens.
C) It is neutralized by H substance.
D) It recognizes any Le^b antigen independent of ABO type.

Answer 1

D

Question 2

Pregnant women usually express which phenotype?

A) Le(a+b-)
B) Le(a+b+)
C) Le(a-b-)
D) Le(a-b+)

Answer 2

C

Question 3

In order for an individual to express Le^b antigen on their red blood cells, they must have inherited which gene?

A) Le
B) Se
C) H
D) All of the above

Answer 3

D

Question 4

An individual from Bombay who has inherited the Le gene will have a phenotype of:

A) Le(a-b-).
B) Le(a+b+).
C) Le(a+b-).
D) Le(a-b+).

Question 5

Persons who inherit the Se and Le genes will have A or B glycolipids in plasma than persons who are Se le.

A) more
B) fewer
C) inactive
D) none of the above

Question 6

What substances would be present in the saliva of a person with the LeLe HH SeSe AA genotype?

A) A, H
B) A, B, H
C) H, B, Le^a, Le^b
D) A, H, Le^a, Le^b

Question 7

Approximately what percentage of the black population is [Le(a-b-)]?

A) 78%
B) 22%
C) 15%
D) 35%

Question 8

What percentage of the white population inherits the Le gene?

A) 50%
B) 90%
C) 10%
D) 25%

Question 9

Individuals who are Le(a-b-) and can develop Lewis antibodies without exposure to Lewis antigens are called:

A) immune mediated.
B) biphasic.
C) naturally occurring.
D) autoantibodies.

Question 10

Which enzyme is responsible for Lewis specificity?

A) L-fucosyltransferase
B) N-acetylglycosyltransferase
C) D-galactosyltransferase
D) N-acetylgalactosyltransferase

Question 11

Anti-Le^a, which is reactive at the Coombs phase, may cause what kind of hemolysis?

A) In vivo
B) In vitro
C) Intravascular
D) None of the above

Question 12

Lewis cell-bound antigens absorbed from plasma onto the red blood cell membranes are:

A) glycoproteins.
B) glycolipids.
C) sphingolipids.
D) ceramides.

Question 13

Which of the following may be a possible cause for the lack of expression of Lewis antigens during pregnancy?

A) Increased ratio of plasma lipoproteins to RBC mass
B) Decreased ratio of plasma lipoproteins to RBC mass
C) Antigenic sites blocked by IgG antibody
D) Antigenic sites blocked by IgM antibody

Question 14

Which of the following statements is false?

A) Lewis antibodies do not bind complement.
B) Lewis antibodies may cause hemolytic reactions if detectable at 37°C.
C) Lewis antibodies are IgM; therefore, they cannot cross the placenta and cause hemolytic disease of the newborn.
D) Lewis antigens are finally developed around age 6.

Question 15

Where are Lewis antigens found?

A) Plasma
B) Saliva
C) Milk
D) All of the above

Question 16

A patient was phenotyped for the presence of Lewis antigens (Le^a and Le^b). A 3+ reaction was observed when patient cells were incubated with anti-Le^a. No reaction was observed with anti-Le^b. Based on these results, the patient's phenotype is and the patient is a of ABH substances.

A) Le(a+b-)/secretor
B) Le(a-b+)/secretor
C) Le(a+b-)/nonsecretor
D) Le(a-b+)/nonsecretor

Question 17

How is Le^b substance formed?

A) L-fucose is added to subterminal N-acetylglucosamine of type 1 H substance.
B) L-fucose is added to subterminal N-acetylglucosamine of type 2 H substance.
C) Le^a and Le^b are codominant alleles located on chromosome 19.
D) Le^b is secreted into plasma in the absence of fucosyltransferase.

Question 18

What does the type 1 chain refer to?

A) Alpha linkage of the number 1 carbon of galactose to the number 3 carbon of N-acetylglucosamine residue of precursor structure
B) Beta linkage of the number 2 carbon of galactose to the number 4 carbon of N-acetylglucosamine residue of precursor structure
C) Beta linkage of the number 1 carbon of galactose to the number 3 carbon of N-acetylglucosamine residue of precursor structure
D) Alpha linkage of the number 1 carbon of galactose to the number 4 carbon of N-acetylglucosamine residue to precursor structure

Question 19

Red blood cells that phenotyped as [Le(a-b-)] are incubated with plasma containing Le^a substance. The red blood cells convert to the phenotype [Le(a+b-)]. Whereas the same red blood cells incubated with saliva containing Le^a substance do not convert. Why?

A) Glycoproteins are not absorbed onto red blood cell membranes.
B) Biochemically, Lewis substances in saliva are glycolipids.
C) Only Le^b substance in saliva can convert phenotypes.
D) Other enzymes found in the saliva interfere with the conversion from Le(a-b-) to Le (a+b-).

Question 20

Lewis antibodies are of what immunoglobulin class?

A) IgM
B) IgG
C) IgA
D) IgE

Question 21

How is Le(y) formed?

A) Fucose-B(1-4) GlcNAc is added to type 1 chain oligosaccharide.
B) Fucose-A(1-3) GlcNAc is added to type 2H precursor substance.
C) Fucose-A(1-4) GlcNAc is added to type 2H precursor substance.
D) Fucose-B(1-3) GlcNAc is added to type 2 chain oligosaccharide.

Question 22

Persons with the Kidd-null phenotype have been found in:

A) Russia.
B) New Zealand.
C) North America.
D) Saudi Arabia.

Question 23

What would be the probable genotype of a patient who phenotypes as ABLe (a-b-)?

A) LeLe sese hh AB
B) lele sese Hh OO
C) lele sese HH AB
D) Lele Sese hh OO

Question 24

P1 antigens:

A) are fully developed at birth.
B) are fully developed at 6 months.
C) take up to 6 or 7 years to develop.
D) none of the above.

Question 25

Lutheran antibodies are rarely associated with causing hemolytic disease of the newborn (HDN) for which of the following reasons?

A) Lutheran antigens are poorly developed at birth.
B) Maternal Lutheran antibodies are absorbed onto glycoproteins on the placenta, decreasing the likelihood of HDN.
C) Lutheran antibodies are generally IgM class and normally do not cross the placenta.
D) All of the above

Question 26

What is the most common Kidd phenotype in the black population?

A) Jk(a+b-)
B) Jk(a+b+)
C) Jk(a-b+)
D) Jk(a-b-)

Question 27

Which of the following is not involved in the Kell blood group system?

A) Js^a
B) K
C) Kp^b
D) Jk^a

Question 28

Where are the Duffy antigens found?

A) Red blood cells
B) Platelets
C) Lymphocytes
D) All of the above

Question 29

Which of the following statements about the Lewis system is not true?

A) The Lewis phenotype depends on whether the Se gene is present.
B) The system is composed of antigen found in secretions
C) Genes of the Lewis system are indicated by LE and le.
D) Secretion of Lewis substance is controlled by the Se gene

Question 30

How does anti-Le^a differ from anti-Le^b?

A) Only anti-Le^a will be produced in Le(a-b-) individuals.
B) Anti-Le^a can bind complement more efficiently.
C) Anti-Le^b is an IgG antibody.
D) Anti-Le^a is an IgM antibody.

Question 31

At which phase are Lewis antibodies usually detected?

A) Immediate spin
B) 37°C
C) Coombs
D) All of the above

Question 32

I and i antigens are found in plasma, serum, and what other possible source?

A) Breast milk
B) Urine
C) Saliva
D) All of the above

Question 33

Why is it relatively easy to find compatible units for a patient with anti-K?

A) Kell is a low-frequency antigen.
B) Kell is a high-frequency antigen.
C) Anti-K does not react at 37°C.
D) Anti-K has a low avidity for its respective antigen.

Question 34

What is found in secretions of Le(a-b-) individuals?

A) Le^a
B) Le^b
C) Both a and b
D) None of the above

Question 35

Red blood cells were treated with ficin to help rule in anti-M from a panel study. Cells not treated reacted at 2+ at immediate spin and 1+ at 37°C. There was no reactivity in the Coombs phase. Ficin-treated cells demonstrated a reaction with patient serum containing anti-M.

A) negative
B) 2+
C) 3+
D) 4+

Question 36

The true Lewis phenotype will normally be detected at what age?

A) Birth
B) 10 days
C) 6 years
D) Not necessarily ever, as circumstances such as pregnancy may alter or mask an individual's true Lewis phenotype

Question 37

Why are Lewis antibodies not generally implicated in hemolytic disease of the newborn?

A) Lewis antigens are well developed at birth.
B) Lewis antibodies are IgM and cannot cross the placenta.
C) Lewis antigens can readily dissociate from the red blood cell upon transfusion of Lewis-positive cells.
D) Lewis antibodies do not bind complement.

Question 38

Why is dosage inconsistent in the Duffy blood group?

A) The genotype could be inherited as Fy^aFy^b or Fy^aFy for Fy(a+b-) red blood cells.
B) Antigen expression is depressed in low ionic strength media.
C) The genotype could be inherited as Fy^aFy^a or Fy^aFy for Fy(a+b-) red blood cells.
D) All of the above

Question 39

Which blood group system is not based on carbohydrates?

A) Lewis
B) Rh
C) P
D) ABO

Question 40

It was discovered that a patient who was to receive two units of packed RBCs had an anti-Le^a circulating in his system. What would be the proper procedure?

A) Anti- Le^a is clinically insignificant, and two units could be issued without further workup.
B) Multiple units should be screened for Le^a antigen, and only two of the units negative for that antigen should be transfused.
C) The two units do not necessarily need to be Le^a-negative but should be crossmatched through at least 37 degrees and crossmatch compatible before given
D) The transfusion should be halted until specially screened units are flown in

Question 41

What is the definition of a blood group system?

A) A group of antibodies produced by alleles at a single gene locus
B) A group of antigens produced by alleles at a single gene locus
C) A group of antibodies produced by alleles at multiple genetic loci
D) A group of antigens produced by alleles at multiple genetic loci

Question 42

What sample requirement is essential for identification of a Kidd antibody?

A) Fresh whole blood
B) Fresh serum or plasma
C) Fasting sample
D) Sample on ice

Question 43

Which of the following distinguishes the recessive LuLu gene from the dominant In(Lu) gene?

A) Normal expression of P₁
B) Abnormal expression of P₁
C) Expression of the Lu(a-b-) phenotype
D) Expression of trace amounts of i antigen

Question 44

Anti-Lu^a reacts at what temperature?

A) Room temperature
B) 37°C
C) AHG
D) All of the above

Question 45

Which of the following is known to enhance K antigen expression in the antihuman globulin test?

A) LISS
B) DTT
C) Albumin
D) Polyethylene glycol

Question 46

How can pathologic anti-I be differentiated from benign anti-I?

A) Immunoglobulin class
B) Binding of complement
C) Broad thermal range of reactivity
D) All of the above

Question 47

What is the function of a GPB-GPA hybrid (anti-Lepore type)?

A) Encodes normal GPA
B) Encodes altered GPB
C) Encodes the COOH end of GPB
D) Encodes the NH₂ end of GPB

Question 48

At what phase of the antihuman globulin test will anti-Kell be detected?

A) IS
B) 37°C
C) AHG
D) All of the above

Question 49

What will happen to I antigen expression when ABH sugars are removed from red blood cells?

A) Increased expression
B) Decreased expression
C) No effect
D) None of the above

Question 50

A blood bank technologist needed to confirm the presence of anti-P₁ in a patient specimen. Fresh cells were not available for use, so an old panel that contained cells positive for P₁ was used. No cells positive for the antigen reacted at any phase of the antiglobulin test, whereas cells from the screening cells showed specificity for the presence of anti-P₁. What is a possible explanation for this?

A) Technician omitted LISS
B) Patient expresses the p phenotype
C) P₁ antigen deteriorates rapidly upon storage
D) Technician forgot to add AHG

Question 51

What does the U in U antigen stand for?

A) unusual
B) universal
C) uniform
D) unique

Question 52

The M and N antigens are found in which glycoprotein?

A) Glycophorin A
B) Glycophorin B
C) Glycophorin C
D) Band 3

Question 53

All of the following are characteristics of Kidd antibodies except:

A) IgG immunoglobulins.
B) ability to bind complement.
C) naturally occurring.
D) exhibit dosage.

Question 54

Infection with which organism is associated with naturally occurring IgM anti-K.

A) Escherichia coli
B) Mycobacterium species
C) Campylobacter coli
D) All of the above

Question 55

Persons who phenotype negative for U antigen lack Ss-SGP because of a partial or complete deletion of .

A) GPA
B) GPB
C) N-acetylneuraminic acid
D) N-acetylgalactosamine

Question 56

When red blood cells are placed in a solution of 2M urea, the red blood cells will lyse. However, it has been shown that which red blood cells are resistant to lysis?

A) Jk(a+b-)
B) Jk(a+b+)
C) Jk(a-b-)
D) Jk(a-b+)

Question 57

Anti-M was detected in a 27-year-old man before surgery. Units negative for M antigen were not available; however, the units were approved for transfusion when major crossmatch using M+N+ donor cells and patient serum resulted in:

A) IS = 1+, 37 = 1+, AHG = 0
B) IS = 1+, 37 = 0, AHG = 0
C) IS = 3+, 37 = 2+, AHG = 1+
D) IS = 2+, 37 = 1+, AHG = 0

Question 58

The Fy5 antigen has been shown to be the result of an interaction between Duffy genes and:

A) Lewis
B) ABO
C) Rh
D) Kidd

Question 59

What is the International Society of Blood Transfusion (ISBT) assignment for the antigen P²?

A) 003001
B) 004001
C) 003100
D) 005001

Question 60

Where are the Kell blood group antigens found?

A) Red blood cells
B) Platelets
C) Lymphocytes
D) All of the above

Question 61

All of the following are grouped with the para-Kell antigens except:

A) K18.
B) K11.
C) K22.
D) K14.

Question 62

The M and N antigens exhibit dosage. Therefore, if a person inherits the homozygous genotype MM, their red blood cells will react with anti-M than/as those of a person with a heterozygous genotype of MN.

A) stronger
B) weaker
C) the same
D) none of the above

Question 63

The Lu gene shares chromosome 19 with what other blood group gene?

A) H
B) Le
C) LW
D) All of the above

Question 64

Persons who express the phenotype P₂ are at risk for developing anti-P₁ when handling what animal species?

A) Dogs
B) Cats
C) Pigeons
D) Mice

Question 65

The genes that code for GPA and GPB are closely linked on the long arm of which chromosome?

A) 9
B) 11
C) 4
D) 15

Question 66

On which malaria receptor site is Duffy antigen dependent?

A) Attachment receptor
B) Junction receptor
C) Ligand receptor
D) None of the above

Question 67

The structures that carry the P antigens also carry which determinants?

A) A
B) I
C) B
D) All of the above

Question 68

Anti-M will react strongest with which cells?

A) M+N-
B) M+N+
C) M-N-
D) M-N+

Question 69

At what age does I antigen become detectable on infant cells?

A) 1 year
B) 18 months
C) 4 years
D) 1 month

Question 70

What characteristic differentiates Ss antigens from MN antigens?

A) Antigens well developed at birth
B) S and s exhibit dosage
C) Enzyme degradation
D) Biochemical structure rich in sialic acid

Question 71

What is the source of anti-M lectin?

A) Bauhinia candicans
B) Dolichos biflorus
C) Iberis amara
D) Bandeiraea simplicifolia

Question 72

A person who inherits alleles Fy^a and Fy^b will carry which antigens on their red blood cells?

A) Only Fy^a antigen
B) Only Fy^b antigen
C) Both Fy^a and Fy^b antigen
D) Neither Fy^a or Fy^b antigen

Question 73

What MN phenotype is found in highest frequency in the white population?

A) M+N+
B) M+N-
C) M-N-
D) M-N+

Question 74

What anemia will result in an increased expression of i antigen, which exceeds that found on control cord cells?

A) Sideroblastic anemia
B) CDA type I
C) CDA type II
D) CDA type III

Question 75

What is the ISBT designation for the Ii blood groups?

A) 200
B) 207
C) 300
D) 310

Question 76

The homozygous phenotype Fy(a+b-) has antigenic Fy sites than heterozygous cells, Fy(a+b+).

A) more
B) fewer
C) weaker
D) none of the above

Question 77

What red blood cell antigens do McLeod individuals express?

A) TracekKp^bJs^bK11
B) KmKx
C) None
D) KkKp^bJs^a

Question 78

What is the etiology of dialysis-associated anti-N?

A) Formaldehyde alters the N antigen so that it is recognized as foreign.
B) Most renal patients express the phenotype M+N-S-s- where most potent forms of anti-N are found.
C) Treatment of renal patients depresses N-antigen expression.
D) None of the above

Question 79

The Kell gene is located on the long arm of which chromosome?

A) 5
B) 7
C) 9
D) 11

Question 80

A patient who has a pathologic autoanti-I must be transfused with:

A) a leukocyte filter.
B) a cold pack.
C) a blood warmer
D) none of the above