P1PK Flashcards
How many antigens does the P1PK blood group system have?
3
How is the P1 antigen made?
It is an indirect product of an enzyme that adds a sugar residue (Gal onto glycolipid.
Where is the genetic locus of P1?
Chromosome 22
What is the % frequency of P1+ in the white population?
79%
What is the % frequency of P1+ in the black population?
94%
What is the % frequency of P1+ in the Vietnamese population?
20%
What is the % frequency of P1- in the white population?
21%
What is the % frequency of P1- in the black population?
94%
What is the % frequency of P1- in the Vietnamese population?
80%
The black population is made up of which people?
African and Caribbean background
What antibody can P1- individuals make?
A naturally occurring anti-P1 and rarely by transfusion
What are the specifications of anti-P1?
- Weak IgM
- Reacts optimally at low temperatures (4-22oC)
- Incapable of complement activation
Why is anti-P1 considered a nuisance antibody?
It can cause delays in ABO grouping (anomalous reverse)
Is anti-P1 clinically significant?
No, unlikely to cause a transfusion reaction and does not cause HDFN
When is anti-P1 clinically significant?
When reactive at 37oC and detected by IAT, but rare!
