Fy antigens developed in utero?
Yes, detected as early as 6 weeks gestation
Which one is more immunogenic? Fya or Fyb?
Fya is 20x more immunogenic
What parasite cannot enter RBCs when you lack Fy antigens
Plasmodium vivax (Malaria)
How do enzymes affect Fy antigens
Destroyed by enzymes
Positive frequency Fya
W 66%
B 10%
Positive frequency Fyb
W 83%
B 23%
Fy antigens present on some nulls
Fy3 Fy5