Hb F-Porto Torres [Agamma75(E19)Ile-->Thr, 136(H14)Ala-->Ser]: a novel variant of the Agamma chain having two substitutions, one being that of Hb F-Sardinia.
The abnormal Hb F-Porto Torres [Agamma75(E19)Ile-->Thr, 136(H14)Ala-->Ser] was observed during a cord blood survey for hemoglobinopathies in North Sardinia. This silent variant showed the same mobility as Hb F-Sardinia in isoelectric focusing (IEF) of the tetramers, whereas the abnormal globin chain was clearly separated by acid-urea-Triton polyacrylamide gel electrophoresis (AUT-PAGE) from the normal Ggamma- and Agamma-globin chains. Separation of the globin chains by reversed phase high performance liquid chromatography (HPLC) indicated the following percentages: Ggamma 68.4, Agamma 14.0, Xgamma 17.6, that strongly suggested the abnormal chain as being a variant of the Agamma-globin. Sequencing of the gamma-globin genes indicated that the mutated gene was in fact an Agamma with two nucleotide replacements, one being the ATA-->ACA (Ile-->Thr) at codon 75 (the so-called AgammaT of the rather common Hb F-Sardinia) and the second the GCA-->TCA (Ala-->Ser) at codon 136. This new variant is the seventh having the sequence of the AgammaT chain with an additional mutation so far described and the third characterized by gene sequencing.
Pirastru
Monica
M
Dipartimento di Scienze Fisiologiche, Biochimiche e Cellulari, e Centro Interdisciplinare per lo Sviluppo della Ricerca Biotecnologia e per lo Studio della Biodiversità della Sardegna e dell'Area Mediterranea, Università degli Studi di Sassari, Italy.
Manca
Laura
L
di Suni
Marcella Palici
MP
Speziga
Silvia Maria
SM
Masala
Bruno
B
D019943:Amino Acid Substitution / Q000235:genetics*; D005319:Fetal Hemoglobin / Q000235:genetics*; D005914:Globins / Q000235:genetics*; D006455:Hemoglobins, Abnormal / Q000235:genetics*; D006801:Humans; D007231:Infant, Newborn; D007558:Italy; D017354:Point Mutation / Q000235:genetics*
D006455:Hemoglobins, Abnormal; C500300:hemoglobin F-Porto Torres; C040337:hemoglobin F Sardinia; D005914:Globins; D005319:Fetal Hemoglobin