Two Fetal Hemoglobin Variants Affecting the Same Residue: HB F-Emirates [^Gγ59(E3)LYS→GLU] and HB F-Sacromonte [^Gγ59(E3)LYS→GLN]

Abstract

Two fast-moving fetal hemoglobin variants were discovered in hematologically normal newborn babies; the first originated in the United Arab Emirates and the second in France. The structural study, carried out by miniaturized techniques of protein chemistry, showed that these two mutations affected the same residue of the G gamma chain, the lysine at position 59(E3) was replaced by glutamic acid in Hb F-Emirates, and by glutamine in Hb F-Sacromonte.

The Use of On‐line Capillary Electrophoresis/Electrospray Ionization with Detection via an Ion Trap Storage/Reflectron Time‐of‐flight Mass Spectrometer for Rapid Mutation‐site Analysis of Hemoglobin Variants

“…A more definitive method used tryptic digestion of Hb with HPLC separation for identification of variant globins based upon a comparison of the tryptic fragments produced. 7,8 In the tryptic fragments of Hb there are 29 digestion peaks for normal adult hemoglobin (HbA), four of which, αT12, αT13, T10, and T12 are insoluble and precipitate out during the digestion preparation; two other single amino acid products, αT8 and T8, are not detected with a UV absorbance detector at 200 nm. 9 Substitution of amino acids between normal Hb and one of its variants results in a change of the position and number of the fragments.…”

Perfusion Chromatography on Reversed-Phase Column Allows Fast Analysis of Human Globin Chains

“…As shown in Tables 1-3, more than one-half of the rare variants we have investigated recovered by eluting an IEF band is sufficient to perform a chromatographic analysis that would provide segregate from the normal corresponding chain. As a consequence, when an abnormal Hb is not readily iden-this answer (14). The simultaneous presence of the two types of g chain demonstrates that the mutant Hb is tified by its electrophoretic mobility pattern, such a rapid chromatography may be of use as an additional an a chain variant.…”

Disorders of the synthesis of human fetal hemoglobin

“…Other G γ variants found in our laboratory are the F‐Emirates [ G γ59(E3)Lys→Glu], HbF‐Columbus‐GA [ G γ94(FG1)Asp→Asn], F‐Calabria [ G γ118(GH1)Phe→Leu] (44, 69–70). HbF‐Emirates was first described in a baby from the United Arab Emirates (71) and the F‐Columbus‐GA in several babies of Caucasian ancestry from Georgia, USA (72).…”