Other Blood Groups- Lewis System

Question 1

Which enzyme is responsible for Lewis specificity?

Answer 1

L-fucosyltransferase

Question 2

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

Answer 2

Glycolipids

Question 3

How is Leb substance formed?

Answer 3

L-fucose substance is added to subterminal acetylglucosamine of 1 H substance

Question 4

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

Answer 4

22%

Question 5

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

Answer 5

Less

Question 6

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

Answer 6

Increased ratio of plasma lipoproteins to red cell mass

Question 7

How does anti-Lea differ from anti-Leb?

Answer 7

anti-Lea can bind complement more efficiently

Question 8

Why is the Le system not implicated in hemolytic disease of the newborn (HDN)?

Answer 8

Lewis antigens are not well developed at birth

Question 9

At which phase are Lewis antibodies usually detected?

Answer 9

Immediate spin

Question 10

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

Answer 10

A, H, Lea, and Leb