How does the Duffy blood group antigen influence the susceptibility to Plasmodium vivax infection?

A By reducing the expression of the Duffy antigen on red blood cells
B By increasing the binding affinity of Plasmodium vivax to red blood cells ✓
C By altering the glycosylation pattern of the Duffy antigen
D By promoting the internalization of the Duffy antigen on red blood cells

Explanation

The Duffy blood group antigen serves as a receptor for Plasmodium vivax, and individuals lacking this antigen (i.e., Duffy-negative) are resistant to infection. However, in individuals with the Duffy antigen, the parasite can bind to and invade red blood cells, increasing the susceptibility to infection.

Source

New England Journal of Medicine
Hematology Hematology: Blood Grouping and Crossmatching Hematology: Blood Grouping and Crossmatching Medium MEDICAL Confidence: high