Deck 5: Rh Blood Group System

Question 1

The frequency of the D-negative phenotype in the population is:

A) 15%.
B) 85%.
C) 50%.
D) 35%.

Answer 1

A
Fifteen percent of the population is D-negative.

Question 2

All of the following can cause the D antigen expression to be weaker except:

A) inheriting the G gene.
B) inheriting the C antigen in trans to the D antigen.
C) an RHD gene that is genetically weaker.
D) partial D expression.

Answer 2

A
The G gene is always inherited when the D or C gene is inherited and has no effect on the strength of the D gene.

Question 3

A patient phenotypes as D+C+E-c-e+. The most likely genotype is:

A) R¹r.
B) R¹R¹.
C) R¹r'.
D) R¹R⁰.

Answer 3

B
R¹R¹ fits the phenotype and is also the more common of the choices given.

Question 4

The inheritance of the Rh antigens are:

A) X-linked recessive.
B) X-linked dominant.
C) autosomal recessive.
D) codominant.

Question 5

Match the following phenotypes with the most probable genotype in the Weiner nomenclature.
a.R₁r
b.R₁R₁
c.R₂R₂
d.rr
DCce

Question 6

The LW antigen expression is typically stronger on __________ cells.

A) D-positive red
B) D-negative red
C) Rh null
D) D-variant

Question 7

How is it genetically possible for a child to phenotype as D-negative?

A) Both parents are heterozygous D-positive.
B) Both parents are homozygous D-positive.
C) Mom is homozygous D-positive, and Dad is heterozygous D-positive.
D) The sibling is D-positive.

Question 8

Red cells that phenotype as D-negative indicate that:

A) they inherited two D genes.
B) there is no genetic material inherited from the RHD gene from both parents.
C) a suppressor gene was inherited that is turning off the D gene expression.
D) reagents currently in use are not detecting the D antigen.

Question 9

Most Rh system antibodies are of which immunoglobulin class?

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

Question 10

Which of the following phenotypes will react with anti-f?

A) rr
B) R₁R₁
C) R₂R₂
D) R₁R₂

Question 11

The numeric Rh4 nomenclature refers to which antigen in the Rosenfield notation?

A) C
B) c
C) e
D) E

Question 12

Testing for the weak D expression is performed by:

A) using anti-Du antisera with an extended incubation.
B) using monoclonal anti-D.
C) performing the indirect antiglobulin test with anti-D.
D) performing the direct antiglobulin test with anti-D.

Question 13

Match the following phenotypes with the most probable genotype in the Weiner nomenclature.
a.R₁r
b.R₁R₁
c.R₂R₂
d.rr
ce

Question 14

The weak D test detects:

A) the Du antigen.
B) the missing D mosaic.
C) a weak D antibody.
D) a weak D antigen.

Question 15

Current theory regarding the genetics of the Rh system suggests that:

A) each Rh system antigen is coded by its own gene locus.
B) Rh system antigens are coded by two closely linked genes.
C) one gene locus with multiple alleles codes for the protein antigens.
D) the Rh system genes are a haplotype that codes for three sets of alleles.

Question 16

Each of the following genotypes is possible for an individual whose red cells react as indicated below except:

A) R¹R²
B) R¹r"
C) R^zr
D) R⁰r'

Question 17

An anti-E was identified in a patient who recently received a transfusion. What other Rh system antibody should be investigated?

A) Anti-G
B) Anti-f
C) Anti-D
D) Anti-c

Question 18

Why is the determination of the D antigen important for women during pregnancy?

A) A D-positive mother can form anti-D during pregnancy that may destroy the D-positive red cells of the fetus.
B) A D-negative mother should be given Rh Immune Globulin to prevent potential formation of anti-D during delivery of a D-positive infant.
C) A D-negative mother may form anti-D if the father of the child is also D-negative.
D) A D-positive mother may pass her red cells to the D-negative fetus and cause hemolytic disease of the fetus and newborn.

Question 19

Anti-D reagent and the Rh control were tested with red cells. Both tests were 2+ agglutination reactions. What is the interpretation of the results?

A) D-positive
B) D-negative
C) Unable to interpret without further testing
D) D-positive if the sample is from a patient

Question 20

How would a donor who tested negative with anti-D reagent in the immediate spin test but positive at antihuman globulin with anti-D reagent be labeled?

A) D-positive
B) D-negative

Question 21

Match the Fisher-Race notation with the correct Weiner notation for the following:
a.Ce
b.CE
c.DCE
d.Dce
R^z

Question 22

Match the following phenotypes with the most probable genotype in the Weiner nomenclature.
a.R₁r
b.R₁R₁
c.R₂R₂
d.rr
DCe

Question 23

Match the Fisher-Race notation with the correct Weiner notation for the following:
a.Ce
b.CE
c.DCE
d.Dce
r^y

Question 24

Match the Fisher-Race notation with the correct Weiner notation for the following:
a.Ce
b.CE
c.DCE
d.Dce
R⁰

Question 25

Match the Fisher-Race notation with the correct Weiner notation for the following:
a.Ce
b.CE
c.DCE
d.Dce
r'

Question 26

Match the following phenotypes with the most probable genotype in the Weiner nomenclature.
a.R₁r
b.R₁R₁
c.R₂R₂
d.rr
DcE