Teruo Harano

High Incidence of α-Thalassemia, Hemoglobin E, and Glucose-6-Phosphate Dehydrogenase Deficiency in Populations of Malaria-Endemic Southern Shan State, Myanmar

Samples from 916 members of various ethnic groups from malaria-endemic southern Shan State, Myanmar, were analyzed for α-thalassemia (α-thal), β -thalassemia (β -thal), abnormal hemoglobin variants, and glucose-6-phosphate dehydrogenase (G6PD) deficiency. Of these subjects, 530 (57.9%) were found to have at least one of these red cell genetic disorders.The overall frequencies for the various red cell genetic disorders were as follows: α-thal, 37.5% (343/916); hemoglobin E (Hb-E), 20.3% (186/916); G6PD-Mahidol, 17.5% (160/916); and β-thal, 0.3% (3/916). The frequencies of combined disorders were 6.9% (63/ 916) for α-thal/Hb-E, 5.7% (52/916) for α-thal/G6PD-Mahidol, 2.8% (26/916) for Hb-E/G6PD-Mahidol, 1.1% (10/916) for α-thal/Hb-E/G6PD-Mahidol, and 0.1% (1/916) for α-thal/β-thal/G6PD-Mahidol. Of the various ethnic and non-ethnic groups, the Bamar population showed the highest frequencies of α-thal (56.9%, 177/311), Hb-E (28.3%, 88/311), and G6PD-Mahidol (21.2%, 66/311) (all duplicated and triplicated cases were included). In addition, 2 new mutations, an a gene triplication (/αααanti3.7; 0.2%, 2/916) and Hb-Neapolis (0.1%, 1/916), were detected. Our results showed that race was the dominant factor affecting the frequencies of red cell genetic disorders in malaria-endemic areas of Myanmar.

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.

Band 4.2 Shiga: 317 CGC → TGC in compound heterozygotes with 142 GCT → ACT results in band 4.2 deficiency and microspherocytosis

Summary. A novel compound heterozygous mutation of 317 CGC → TGC with 142 GCT → ACT in human red cell band 4.2 deficiency is described. A proband and his son suffered from compensated haemolysis with nearly complete deficiency of red cell band 4.2. Their red cell morphology exhibited microspherocytosis resembling classic hereditary spherocytosis (HS). Sodium dodecylsulphate‐polyacrylamide gel electrophoresis (SDS‐PAGE) showed band 4.2 to be nearly missing (< 1% of normal controls) with the presence of 74 kU and 72 kD isoforms in trace amounts. Other family members (daughters older and younger than the son) exhibited nearly normal amounts of 72 kD as a wild form of band 4.2 on SDS‐PAGE with the presence of the 74 kD isoform in a trace amount. The proband and his son demonstrated two compound heterozygous mutations in trans: i.e. nucleotide (nt) 949 CGC → TGC (codon 317 Arg → Cys) in exon 7 and nt 424 GCT → ACT (codon 142 Ala → Thr) in exon 3 of the band 4.2 gene. The two daughters demonstrated only the mutation of nt 949 CGC → TGC in exon 7 in heterozygous states, but no 142 mutation. Therefore the proband and his son were compound heterozygotes of these two mutations in trans. It is interesting to note that the 74 kD isoform of band 4.2 protein existed in a trace amount in the two daughters in spite of the absence of the 142 Ala → Thr mutation. In addition, even in the presence of the 142 mutation in one allele in the proband and his son, their red cell morphology demonstrated classic HS with microspherocytosis, although a homozygous state of the 142 mutation known as the Nippon type of band 4.2 deficiency exhibits ovalostomato‐cytosis.

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.

Hemoglobin Takamatsu (β120 (GH 3) Lys → Gln): A New Abnormal Hemoglobin Detected in Three Unrelated Families in the Takamatsu Area of Shikoku

A survey of hemoglobinopathies which was carried out in the Takamatsu district during the period from January to August 1979 detected six families with abnormal hemoglobins. Approximately 6010 inhabitants were screened.Three of these families had the same new Hb variant (Hb Takamatsu β120 Lys → Gln) that has not been previously reported.Existence of a blood relationship among these three families could not be established even after careful family studies.This abnormal hemoglobin was not associated with adverse symptoms and gave normal hematologic findings in the carriers.The isopropanol test was negative, oxygen affinity was within the normal range, and biosynthetic ratio in reticulocytes was around 1.0.One of the difficulties in the structural analysis of this hemoglobin was related to complete superposition of abnormal βXT-12b,13 on a βT-8.9 peptide in the fingerprint of the trypsin digest of aminoethylated aberrant βX chain. This was overcome by collection of abnormal tryptic 3 core (βXT-10-13) from un...