Immunohematology Unit 1

O Frequency

45%

A Frequency

40%

B Frequency

11%

AB Frequency

4%

O inheritance

A-2-L-fucosyltransferase adds L-fucose

A Inheritance

a-3-N-acetylgalactosaminyltransferase adds N-acetyl-D-galactosamine (GalNAc)

B Inheritance

a-3-D-galactosyltransferase adds D-galactose

A3 Group

Weak a-3-N-acetyltransfersse. Mixed field pattern of agglutination w Anti-A and B. A + H for secretor testing.

Ax Group

No A transferase, may be negative with Anti-A. Anti-A1 present. H for secretor.

Group I

Weak or missing antibodies. Resolution by incubating reverse typing.

Group II

Weak or missing antigens. Resolution by enhancing front typing.

Group III

Protein or plasm abnormalities. Cause 2+ in all they shouldn’t. Check Ab screens, ID cold agglutinins.

Rh C

70%

Rh c

80%

Rh E

30%

Rh e

98%

Genetic Weak D

Inherited fewer D antigen sites. Still Rh+

C in trans to RHD

Dc-/dC-. Rh+ can be transfused.

Partial D

Missing portions of D antigen, can produce Anti-D if exposed. Rh- transfused.

Del Phenotype

Mutated RHD alters expression. Undetectable Rh, appears Rh-

Rh null

All Rh alleles are missing. RHAG mutation or RHD deletion w mutations in both RHCE genes. Stomatocytes. Only null can give blood

Rh mod

Weakened expression of all Rh antigens.

f(ce)

DCe/dce.

004007 Ce

Dce/dCe

G

Antigenic determinant is on both C and D antigen.