Hb J-Cape Town [alpha92(FG4)Arg-->Gln (alpha1), CGG-->CAG] in Southern Italy found in a patient with erythrocytosis.
A high oxygen affinity hemoglobin (Hb) variant, Hb J-Cape Town [alpha92(FG4)Arg-->Gln (alpha1), CGG-->CAG] was identified in a 30-year-old woman patient from Cosenza (Southern Italy) who had previously been diagnosed with juvenile polycythemia in other hospitals. The occurrence of the variant Hb was assessed by both cation exchange chromatography and liquid chromatography-mass spectrometry (LC-MS) analyses. A detailed structural and functional characterization of the variant was performed at both the protein and DNA level. Structural investigation of the Hb variant by mass spectrometric methodologies and peptide sequencing identified the amino acid replacement as Arg-->Gln at alpha92. The corresponding DNA mutation CGGCAG was assigned to codon 92 of the alpha1 gene by DNA sequencing. These findings highlight the importance of investigating the hypothesis of a high affinity variant in the presence of a polycythemia so as to avoid unnecessary bone marrow examination or radioactive treatment. This report represents the first observation of the Hb J-Cape Town variant in Italy.
Pagano
Leonilde
L
Centro Microcitemie A. Mastrobuoni, Azienda Ospedale Cardarelli, Napoli, Italia.
Flagiello
Angela
A
Tedesco
Roberta
R
Ammirabile
Massimiliano
M
Pollio
Filiberto
F
Prossomariti
Luciano
L
Giambona
Antonino
A
Passarello
Cristina
C
Pucci
Piero
P
D000328:Adult; D019943:Amino Acid Substitution; D001120:Arginine; D004247:DNA / Q000097:blood / Q000235:genetics / Q000302:isolation & purification; D017931:DNA Primers; D005260:Female; D014644:Genetic Variation; D005973:Glutamine; D006448:Hemoglobin J / Q000235:genetics*; D006801:Humans; D007558:Italy; D008297:Male; D010446:Peptide Fragments / Q000302:isolation & purification; D011086:Polycythemia / Q000097:blood / Q000235:genetics*; D020641:Polymorphism, Single Nucleotide
D017931:DNA Primers; D010446:Peptide Fragments; D005973:Glutamine; D006448:Hemoglobin J; D004247:DNA; C039483:hemoglobin J Cape Town; D001120:Arginine