K. Harano

Hb Okazaki [β93(F8) Cys → Arg], a new hemoglobin variant with increased oxygen affinity and instability

A new abnormal hemoglobin, Hb Okazaki [β93(F9) Cys → Arg], with an amino acid substitution at the tyrosine pocket of the β chain as well as at the α2β1 contact of the quaternary structure of molecule, was discovered in a Japanese man. This hemoglobin showed increased oxygen affinity and molecular instability.

Hemoglobin Okayama [β-2 (NA 2) His → Gln]: A new ‘silent’ hemoglobin variant with substituted amino acid residue at the 2,3-diphosphoglycerate binding site

A new ‘silent’ abnormal hemoglobin, Hb Okayama [β2 (NA 2) His → Gln], happened to be discovered in a diabetic Japanese female living in Okayama Prefecture, Japan, in the course of glyco‐Hb measurement of the blood samples of diabetic patients. This variant did not differ from Hb A by conventional electrophoretic tests. Only the isoelectric focusing on PAG plate for the determination of glyco‐Hb and the cation exchanger chromatography were successful in the separation of this abnormal variant from Hb A and glyco‐Hb. Functional study of the whole blood demonstrated a slight increase of oxygen affinity.

Hb Fukuoka [β2(NA2)HISTYR]: A New Nutation at the 2,3-Diphosphoglycerate Binding Site

Two abnormal hemoglobins (Hbs) with a substituted amino acid residue at the 2nd position of the B chain, a part of the 2,3-diphosphoglycerate (2,3-DPG) binding site, have been reported: Hb Deer Lodge (His+Arg) (1) and Hb Okayama (His-Gln) (2). In 1985, we found a new abnormal Hb during assay of Hb A1c and Hb A1 by high performance liquid chromatography (HPLC) in a 38-year-old Japanese female patient suffering from diabetes mellitus. This abnormal Hb was designated Hb Fukuoka [B2(NA2)HisTyr] after the name of the city where the patient lived. Herein, we describe the structural analysis and functional properties of this Hb.

Hb Toranomon [beta 112(G14)Cys->Trp] : a new unstable electrophoretically silent hemoglobin

We describe a silent and unstable hemoglobin variant, Hb Toranomon, which was discovered by high performance liquid chromatography in an apparently healthy Japanese male during a Hb A1c assay. Isoelectrofocusing of his hemolysate and chromatographic separation of globin on a CM-cellulose column revealed no abnormality. The isopropanol precipitation test gave a positive result. Amino acid analysis of all peptides isolated from the tryptic digests of the aminoethylated and non-aminoethylated beta chain (beta A + beta X) by reversed phase high performance liquid chromatography indicated a substitution of Cys-->Trp at position 112 of the beta chain, which was confirmed by protein sequencing. cDNA sequencing showed the nucleotide sequence of the beta 112 codon to be TGG instead of TGT, confirming the amino acid substitution described above. The globin biosynthesis ratio (beta/alpha) was 1.00.

Hb Yamagata [B132(H10)LYS-ASN]: A New Abnormal Hemoglobin in a Japanese Family

During routine high performance liquid chromatography (HPLC) assay using TSKgel Glyco-columns (4.0 mm ID. x 15 cm, Tosoh Co., Tokyo, Japan) of the glycosylated Hb A1c of patients with diabetes mellitus, we encountered a 57-year-old Japanese female whose total hemoglobin (Hb) contained about 45% abnormal Hb fraction including Hb A1c. Isoelectrofocusing (IEF, pH range 6-9) of her hemolysate distinctly revealed an abnormal Hb band which had migrate to the anodic side of Hb A (Fig. 1). The primary structure of the abnormal 3 chain was a substitution consistent with the substitution of LysAsn at B132 by reversed phase HPLC of the tryptic digest and nucleotide sequencing of the B-globin gene. This is the first report of such a Hb variant (1) which has been named Hb Yamagata [Bl32(H10)Lys-Asn] after the prefecture in which the carrier lived. The structural analysis and functional properties of this Hb are described herein.

A wider molecular spectrum of β-thalassaemia in Myanmar

Summary.  Two hundred and nine beta‐thalassaemia (β‐Thal) alleles of 158 unrelated Myanmar patients (107 HbE‐β‐Thal; 51 β‐Thal major) were analysed for β‐globin gene mutations. Amplification refractory mutation system (ARMS) characterized six β‐thal mutations known to Myanmar [βIVSI‐1(G→T), codon 41/42(–TCTT), βIVSI‐5(G→C), codon 17(A→T), βIVS II‐654(C→T), and −28 Cap (A→G)] in 166/209 (79·4%) alleles. DNA sequencing of 24 alleles from 43 ARMS‐negative samples (20·6%) identified an additional 12 new mutations, to produce a total of 18 different mutations. Nineteen alleles (9·1%) remained for further characterization. The molecular spectrum of Myanmar β‐Thal is wider and more heterogeneous than previously reported.

Short Communication:Hemoglobin Machida [β6 (A3) Glu → Gln], a New Abnormal Hemoglobin Discovered in a Japanese Family: Structure, Function and Biosynthesis

This report describes a new abnormal hemoglobin discovered in a 43-year-old Japanese female living in Machida City, Tokyo Capital City, in October 1981. Hematological study of the propositus, who was clinically healthy, showed neither microcytic hypochromic anemia due to iron deficiency, nor hemolytic tendencies, in spite of slightly decreased serum iron and slightly increased reticulocyte count (WBC 4.3 × 109/1, RBC 4.46 × 1012/1, Hb 13.6 g/dl, PCV 0.388 1/1, MCV 87 fl, MCH 30.8 pg, MCHC 35.2 g/dl, reticulocyte count 1.4%, total bilirubin 0.3 mg/dl, serum iron 65 μg/dl, TIBC 329 μg/dl). Target cells were not seen on peripheral blood smears. Family study disclosed that her son (10 year old) was a carrier of the same abnormal hemoglobin. He was also apparently healthy and hematologically normal.

HB Kurosaki [α7(A5)LYS→GLU]: A New α Chain Variant Found in a Japanese Woman

There are many abnormal hemoglobins (Hbs) which have been discovered during the assay of glycosylated Hb (Hb A1c) of the peripheral blood by use of a cation exchange high performance liquid chromatography (HPLC) system. We have encountered a patient whose peripheral blood showed the presence of an abnormal Hb peak on an HPL chromatogram. Structural analysis demonstrated that the Hb had an amino acid substitution of Lys→Glu at the 7th position of the α chain. This variant has not been reported before (1). We have named it Hb Kurosaki or α7(A5)Lys→Glu after the name of the city where the patient lived.

HB Kanagawa [α40(C5)LYS→MET]: A New α Chain Variant with an Increased Oxygen Affinity

An abnormal hemoglobin was suspected in a 70-year-old Japanese male with cerebral infarction and erythremia with high performance liquid chromatography assay of Hb A1c. The hemoglobin variant migrated to the anode more rapidly than Hb A. Structure determination studies, including amino acid analysis of the abnormal pep-tide and DNA sequencing of a partially cloned α-globin gene, demonstrated that it is a new hemoglobin variant which has been named Hb Kanagawa [α40(C5)Lys→Met]. This variant showed an increased oxygen affinity, decreased heme-heme interaction, and a lowered 2,3-diphosphoglycerate effect relative to normal.

A new hemoglobin variant, Hb Mito [β144(HC 1)Lys → Glu], with increased oxygen affinity

A new abnormal hemoglobin, Hb Mito [β144(HC 1)Lys → Glu], with an amino acid substitution in the 2,3‐DPG pocket, was discovered in a Japanese female. This hemoglobin showed increased oxygen affinity, and decreased organic phosphate and Bohr effects, while the Hill constant n was normal.