S. S. Chen

The Identification of Five Rare β-Chain Abnormal Hemoglobins by High Performance Liquid Chromatographic Procedures

The detection, quantitation, and characterization of five relatively rare beta chain abnormal hemoglobins mainly by high performance liquid chromatographic procedures are described. The variants involved are Hb City of Hope (beta 69 Gly----Ser), Hb Austin (beta 40 Arg----Ser), Hb Leiden (beta 6 or 7 Glu----0), Hb Louisville (beta 42 Phe----Leu), and Hb Presbyterian (beta 108 Asn----Lys). Some clinical and hematological data are also included.

Hb F-Tokyo or α2GΓ234(B16) Val→Ile, A Silent Γ Chain Variant Detected by Reverse Phase high Performance Liquid Chromatography

Hb F-Tokyo with a Valine→Isoleucine replacement at position γ34(B16) is a Gγ chain variant which was discovered by reverse phase chromatography as this method permitted the nearly complete separation of the three types of γ chain. The chemical characterization was greatly facilitated by the use of a larger, preparative, HPLC column which allowed the isolation of sufficient quantities of the different γ chains.

Hb Doha or α2β2[X-N-Met-1-(NA1)Val → Glu]; a new β-chain abnormal hemoglobin observed in a Qatari female

Abstract Structural analysis of a fast-moving hemoglobin variant, present in three members of a Qatari family, identified a Val → Glu substitution at position 1 (NA1) of the β-chain. The introduction of this glutamic acid residue prevents the removal of the initiator methione, thus extending the N-terminus by one residue to Met-Glu-His-Leu-Thr-. THe methionine residue is blocked by an as yet not completely identified molecule. The presence of the variant in a heterozygote does not have clinical consequences.

Hb Chicago or α2136(H19)LEU+METβ2 and A-Gγ-GGMGlobin GWE Arrangewznt in a Black Family

Hb Chicago is a newly discovered hemoglobin variant which was present in a Black newborn baby and her father. The leucine residue at alpha 136, which normally participates in the contact with the heme group, is replaced by a methionine residue. The two heterozygotes were clinically well with normal hematological data. Isolation of the alpha X and alpha A chains by reverse phase high performance liquid chromatography and hydrolysis of these chains with dilute formic acid at 110 degrees C for 24 hours, followed by separation of the resulting peptides by reverse phase high performance liquid chromatography, greatly facilitated the final identification of the abnormality. The baby and both parents had a -G gamma-G gamma-globin gene arrangement on one chromosome (normal: -G gamma-A gamma-) which explains the high G gamma values in the Hb F of these three persons.

Some notes about HB Q-India and HB Q-Iran

(1986). Some notes about HB Q-India and HB Q-Iran. Hemoglobin: Vol. 10, No. 2, pp. 215-219.

HB F-Pendergrass, AH AΓI Variant with a Pro→Arg Substitution at Position Γ36(C2)

(1985). HB F-Pendergrass, AH AΓI Variant with a Pro→Arg Substitution at Position Γ36(C2) Hemoglobin: Vol. 9, No. 1, pp. 73-77.

Hemoglobin H Disease in two Turkish Females and one Iranian Newborn

Recent advances in molecular biology has resulted in the characterization of different forms of α-thalassemia (α-thal). Deletion, or occasionally dysfunction, of one or both α globin genes, which are located on the short arm of chromosome #16 (l), will lead to an α chain deficiency with variable alterations in red cell indices. α-Thal-2 or αα/-α results from deletion of one of the two a globin genes, i.e. either the leftward or 4.2 kb deletion involving the α2 globin gene or the rightward or 3.7 kb deletion which involves the 3′ segment of the α2 gene, the 5 ′ segment of the a1 gene and intergenic DNA. α-Thal-1 or αα/- results from larger deletions involving segments of DNA which contain both the α2 globin gene and (part of) the α1 globin gene. The various types are due to misalignment between two strands of DNA from two separate chromosomes during meiosis followed by an unequal crossover generating chromosomes with a single (or no) functional a globin gene or with triplicated a globin genes (2, and refer...

HB f-cobb OR α2aγ237(c3)TRP→GLY

An electrophoretically slow-moving hemoglobin (Hb) component was found in the red cell lysate from a Caucasian newborn (#50777) which is characterized by a Trp→Gly substitution at position 37 (C3) of the Aγ chain. Since such a replacement has not been observed before, the variant was named F-Cobb after the county of residence.