New genotypes in Fy(a-b-) individuals: nonsense mutations (Trp to stop) in the coding sequence of either FY A or FY B.
Duffy blood group antigens are carried on a glycoprotein that is predicted to pass through the erythrocyte membrane seven times and is a promiscuous chemokine receptor. The Fy(a- b-) phenotype is present in two-thirds of African-American Blacks but is rare in Caucasians. In Blacks, the phenotype is due to a non-functional GATA-1 motif in the FY B, which silences the gene in erythrocytes but not in other tissues, and these patients do not generally make anti-Fyb or anti-Fy3. We describe here the molecular analysis of FY in three unrelated Caucasians who were studied because they had strong anti-Fy3 in their serum. Each was found to have a point mutation that was predicted to change a tryptophan to a premature stop codon in the coding sequence. In one patient (patient 1), the nonsense mutation was at nucleotide 287 of the major transcript in FY A; in another (patient 2), it was at nucleotide 407 in the major transcript of FY B; and in a third (patient 3), it was at nucleotide 408 of the major transcript of FY A.
Rios
M
M
New York Blood Center, New York, NY 10021, USA. mrios@nybc.org
Chaudhuri
A
A
Mallinson
G
G
Sausais
L
L
Gomensoro-Garcia
A E
AE
Hannon
J
J
Rosenberger
S
S
Poole
J
J
Burgess
G
G
Pogo
O
O
Reid
M
M
D000368:Aged; D000369:Aged, 80 and over; D018389:Codon, Nonsense / Q000235:genetics; D018388:Codon, Terminator / Q000235:genetics; D004375:Duffy Blood-Group System / Q000235:genetics*; D017809:Fatal Outcome; D005260:Female; D005838:Genotype; D006801:Humans; D008297:Male; D008875:Middle Aged; D017354:Point Mutation / Q000235:genetics*; D016133:Polymerase Chain Reaction / Q000379:methods; D012150:Polymorphism, Restriction Fragment Length
D018389:Codon, Nonsense; D018388:Codon, Terminator; D004375:Duffy Blood-Group System