antigens are manufactured by tissue cells, secreted into the body fluids, and are absorbed (stuck) onto the RBC membrane.
To have Lewis antigens these genes must be present
Lewis genes AND the secretor (Se) gene
3 ways Lewis antigens differ
1. Lewis antigens are not intrinsic to the RBC membrane produced during the cell development. Antigens are produced by tissue cells and are absorpted onto the RBCs. 2. A person's Lewis phenotype is NOT determined SOLELY by genes at the Lele locus. Hh and Sese loci are involved with the Lele locus 3. The amount of Lewis antigen expression on the RBC varies according to the cell's ABO phenotype.
What Chromosome is the Le gene on?
Short arm of chromosome 19 (90% white population)
Genes needed to express Le-a
Just Le gene
Genes needed to express Le-b
Le and Se genes
22% of the population
72% of the population
Le-b secretes what antigens and what antigens are on the RBC
both Lea and Leb soluble antigens are present in the secretions and plasma but only Leb appears on the RBC surface.
no Le antigens are present on the RBC or secretions... (nonfunctional or partially active Lewis transferase)