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Duffy glycoprotein is a receptor for these 2 things cytokines and Plasmodium vivax
Duffy antigen frequencies by race Fya: 66% Caucasians, 10% Blacks, 99% Asians Fyb: 83% Caucasians, 23% Blacks, 18.5% Asians Fy3: 100% Caucasians, 32% Blacks, 99.9% Asians
Frequency of Duffy phenotypes The Duffy null phenotype, Fy(a-b-), is very rare in Caucasians but is found in 68% of Blacks. Fy(a+b+): 49% Caucasians, 1% Blacks, 9% Chinese Fy(a-b+): 34% Caucasians, 22% Blacks, <1% Chinese Fy(a+b-): 17% Caucasians, 9% Blacks, 91% Chinese
Antibody type for Duffy antibodies IgG
Do Duffy antibodies bind complement? No
The Duffy null phenotype, Fy(a-b-), is the most common phenotype in this population. most common phenotype in Blacks
Why is there racial variation in the distribution of Duffy antigens? Result of a positive selection pressure—absence of Duffy antigens on RBCs makes the RBCs more resistant to invasion by p.vivax
Worldwide the Plasmodium species that is responsible for the majority of fatal cases P. falciparum
In Asia and the Americas, which Plasmodium species is a more common cause of malaria P. vivax
How does Plasmodium vivax enter an RBC? By binding to N-terminal extracellular domain of the Duffy glycoprotein through cysteine-rich region of Duffy binding protein (DBP). Individuals with the Duffy null phenotype do not express Duffy protein on RBCs and are immune to P. vivax infection.
The Duffy locus, FY, is located on chromosome 1
genetic background that give rise to the Duffy negative phenotype Fy(a-b-) in blacks Mutation in promoter region of FYB allele abolishes expression of Duffy glycoprotein in RBCs, protein still produced in other types of cells.
genetic background that give rise to the Duffy negative phenotype Fy(a-b-) in which no Duffy antigens are expressed in RBCs or tissues point mutation introduces premature stop codon into coding sequence.Unlikely that truncated Duffy protein is transported to cell surface, and likely that Duffy protein would be absent from all tissues in individuals who carry this type of mutation.
What is the severity of Hemolytic disease of the newborn caused by anti-Duffy antibodies Tends to be mild in nature.
Created by: jfshikle