d. The rare individuals of phenotype p, previously called Tj(a-), have anti-PP1pk
(previously called anti-Tja) in their serum. Antibodies with this specificity are nearly
always hemolysins capable of causing hemolytic transfusion reactions and hemolytic
disease of the newborn. The rare individuals having the Pk phenotype have anti-P in
their serum reacting with P1 and P2 cells, but not with p cells. Table 2-22 reviews the
serologic behavior of the P system antibodies.
Table 2-22. Serologic behavior of P system antibodies.
2-34. DUFFY BLOOD GROUP SYSTEM
a. Anti-Duffy (Fya) reacts with the red blood cells of about 66Whites. Anti-Fyb,
specific for the antithetical antigen, reacts with about 80Fyb, with a locus on
chromosome one. A third "silent" allele at this locus has a high frequency among Black
subjects. Table 2-23 shows the phenotypes observed when the two antiserums are
b. "In vitro" reactions of Fya and Fyb antigens are greatly weakened when red
blood cells are treated with proteolytic enzymes. Both anti-Fya and anti-Fyb react best in
the antiglobulin test; both have caused hemolytic transfusion reactions as well as
hemolytic disease of the newborn (see Table 2-24).