ABO Review Sheet Information

Question 1

What are the three allels of the ABO system?

Answer 1

ABH

Question 2

Name the four phenotype of the ABO system.

Answer 2

A
B
O
AB

Question 3

Name the six genotypes of the ABO system

Answer 3

AA AO
BB BO
OO AB

Question 4

Which ABO genes are dominant over O

Answer 4

A and B

Question 5

Which ABO gene is recessive?

Answer 5

O

Question 6

Which ABO genes are codominant?

Answer 6

A and B

Question 7

Which antigen must be present on RBCs in order for expression of ABO antigens?

Answer 7

H

Question 8

What is the immunodominant sugar associated with the H antigen?

Answer 8

L-fucose

Question 9

What is the immunodominant sugar associated with the A antigen?

Answer 9

N-acetylD-galactosamine (GalNac)

Question 10

What is the immunodominant sugar associated with the B antigen?

Answer 10

D-galatose (Gal)

Question 11

Describe the outcome of an hh person

Answer 11

Bombay

Question 12

Describe the outcome if a Bombay person recieves O blood.

Answer 12

O RBCs will be destroyed due to H antigen on the transfused blood. Anti-A, Anti-B, Anti-AB and Anti-H in serum.

Question 13

Forward Typing
Bombay
Group O

Answer 13

Anti A Anti-B Anti H
0 0 0
0 0 4+

Question 14

Reverse Typing
Bombay
Group O

Answer 14

A cells B cells
4+ 4+
4+ 4+

Question 15

What are the two major subgroups of group A and their frequency?

Answer 15

A1 (80%)

A2 (20%)

Question 16

What plant lectin is used to differentiate between subgroups A1 and A1?

Answer 16

Dolichos bifloris

Question 17

Name some examples of weak group A phenotypes.

Answer 17

A3, Ax, Aend, Am, Ay, Ael, Aint, Abantu, Afinn

Question 18

What antibodies are associated with blood group A?

Answer 18

anti-B

Question 19

What antibodies are associated with blood group A?

Answer 19

anti-A

Question 20

What antibodies are associated with blood group O?

Answer 20

anti-A
anti-B
anti-AB

Question 21

What antibodies are associated with blood group AB?

Answer 21

none

Question 22

In babies, when do ABO antibodies start to develop?

Answer 22

3-6 months

Question 23

How do ABO antibodies develop?

Answer 23

Naturally occuring IgM due to the actions of E. coli in the gut. May also develop anti-IgG through pregnancy or tansfusion.

Question 24

Name two classes of ABO antibodies

Answer 24

IgM and IgG

Question 25

Describe anti-AB

Answer 25

Seperates antibodies (not a combination). Foudn in the serum of type O persons. May react more strongly that anti-A or anti-B with some A and B subgroups.

Question 26

Give examples of people who may lack ABO antibodies

Answer 26

``` Newborns or very old leukemia patients hypogammaglobulinemia Immunosuppressed Bone Marrow transplant patients ```

Question 27

A serum grouping

Answer 27

A cells negative B cells 4+ anti-B

Question 28

B serum grouping

Answer 28

A cells 4+ B cells negative anti-A

Question 29

O serum grouping

Answer 29

A cells 4+ B cells 4+ anti-A, anti-B, anti-AB

Question 30

AB serum grouping

Answer 30

A cells negative B cells negative no antibodies formed

Question 31

Reasons for weak or missing antibodies

Answer 31

``` Age or disase hypgammaglobulinemia immunosuppressed bone marrow transplat malignant lymphomas Substances in places (ex. excess BGSS) ```

Question 32

Give examples of cold-reactive autoantibodies

Answer 32

Panagglutination Strong autoanti-I autoantibodies including anti-I and anti-H

Question 33

Give examples of cold-reactive antibodies

Answer 33

May be anti-A1 due to subgroup of A and B | alloantibodies including anti-M, and Lea, and antiP1

Question 34

Give examples of Rouleaux

Answer 34

Wharton's Jelly plasma expanders (Dextran) Multiple Myeloma Waldenstrom's Macroglobulinemia

Question 35

What are some MISC causes of inaccurate ABO testing?

Answer 35

Substances in plasma (BGSS) Flase positive from Acriflavin dye (anti-B) and Wharton's Jelly Polyagglutination (T, TN, TK activation) Aquired B antigens (colon/rectale cancer) Rare antibody in antisera Reagent red cell deterioration Positive direct antiglobulin test Transfusion of Non-ABO Identical Plasma Products

Question 36

Define seretor

Answer 36

An individual who is capable of secreting soluble, glycoprotein ABH-substances into saliva and other body fluids.

Question 37

Secretor gene vs. Nonsecretor gene

Answer 37

SeSe, Sese | sese

Question 38

What are the two blood groups involved in secretor status?

Answer 38

ABO and H

Question 39

Define lectin

Answer 39

Proteins present in plants, usually seeds, which bind specifically to carbohydrate determinants and agglutinate RBCs through their cell surface of oligosaccharide determinants.

Question 40

Name the H lectin

Answer 40

Ulex europaeus

Question 41

What percentage of the populator are secretors?

Answer 41

80%