α78(EF7)Asn→Asp is a Posttranslational Modification in Hb J-Singapore [α78(EF7)Asn→Asp;α79(EF8)Ala→Gly]

In Hb J-Singapore, the α78(EF7)Asn→Asp and α79(EF8)Ala→Gly substitutions were initially thought to be genetic mutations. Subsequent studies on other similar hemoglobin variants suggested that the Asn→Asp change was a posttranslational modification. Nevertheless, lack of DNA evidence made it difficult to confirm the deamidation in Hb J-Singapore. We recently encountered a female patient with Hb J-Singapore trait. In this report, we present electrospray mass spectrometry and DNA data to confirm the α78(EF7)Asn→Asp is indeed a posttranslational modification.     

Hb Sallanches [α104(G11)Cys→Tyr,TGC→TAC (α2)]: An Unstable Hemoglobin Variant Found in an Indian Child

We report the fourth observation of Hb Sallanches [α104(G11)Cys→Tyr, TGC→TAC (α2)], an unstable α chain variant of intermediate severity in the homozygous state. Heterozygosity occasionally produces mild hypochromia and microcytosis in some patients. A balanced β/α ratio, found in previously reported cases, points to unstable αβ dimers formed as a result of the Cys→Tyr substitution at the α1β1 contact site in this hemoglobin (Hb) variant. Our patient, and the previous two of the three cases reported in patients of Pakistani origin, points to a common population stock, separated by the mass population migration which occurred during the partition of Pakistan and India in 1947.     

Hb J-CAPE TOWN [α92(FG4)Arg→Gln (α1), CGG→CAG] in Southern Italy Found in a Patient with Erythrocytosis

A high oxygen affinity hemoglobin (Hb) variant, Hb J-Cape Town [α92(FG4)Arg→Gln (α1), CGG→CAG] was identified in a 30-year-old woman patient from Cosenza (Southern Italy) who had previously been diagnosed with juvenile polycythemia in other hospitals. The occurrence of the variant Hb was assessed by both cation exchange chromatography and liquid chromatography-mass spectrometry (LC-MS) analyses. A detailed structural and functional characterization of the variant was performed at both the protein and DNA level. Structural investigation of the Hb variant by mass spectrometric methodologies and peptide sequencing identified the amino acid replacement as Arg→Gln at α92. The corresponding DNA mutation CGG→CAG was assigned to codon 92 of the α1 gene by DNA sequencing. These findings highlight the importance of investigating the hypothesis of a high affinity variant in the presence of a polycythemia so as to avoid unnecessary bone marrow examination or radioactive treatment. This report represents the first observation of the Hb J-Cape Town variant in Italy.     

Hb Barika [α42(C7)Tyr→His (α2)] Leads to an α+-Thalassemia-like Syndrome

In human deoxyhemoglobin (deoxyHb), the hydrogen bond between Aspβ99(G1) and Tyrα42(C7), located in the α1β2 interface, is crucial for the stability of the T structure. All the variants that could arise from a single point mutation affecting codon β99 have already been observed, leading always to erythrocytosis. Conversely, up to now, Hb Barika is the only example found in a patient in whom the α42 is mutated. From a biochemical point of view, for theoretical reasons, this substitution has already been extensively studied on recombinant hemoglobin (rHb). In the patient, Hb Barika is expressed at a level lower than expected for an α2 gene variant and leads to an α⁺-thalassemic-like syndrome.     

Tumor-related elevation of serum (α1→3)-l-Fucosyltransferase activity in gastric cancer

Summary (13)-l-Fucosyltransferase activity was measured in serum samples from 90 gastric cancer patients, 10 patients with benign diseases and 100 healthy controls. The enzyme activity was significantly elevated in the serum samples of patients with cancer compared to those from patients with benign diseases (P<0.01) and healthy controls (P<0.001). The elevation of the enzyme activity was found to correlate strongly with the clinical stage of disease. The sensitivity of (13)-l-fucosyltransferase was also demonstrated to be high in comparison with the tumor-associated antigens, such as carcinoembryonic antigen and sialylated Lewis X-i. Follow-up studies of (13)-l-fucosyltransferase in 11 cancer patients with disease at different stages showed that the enzyme activity could be useful for monitoring the postsurgical course of the disease. These results suggest that (13)-l-fucosyltransferase activity has a clinically important potential as a tumor marker in gastric cancer.Abbreviations Gal d-galactose - Fuc l-fucose - GlcNAc N-acetyl-d-glucosamine - HEPES 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid     

Description of Two New α Variants: Hb Canuts [α85(F6)Asp→His (α1)] and Hb Ambroise Pare [α117(GH5)Phe→Ile (α2)]; Two New β Variants: Hb Beaujolais [β84(EF8)Thr→Asn] and Hb Monplaisir [β147 (Tyr-Lys-Leu-Ala-Phe-Phe-Leu-Leu-Ser-Asn-Phe-Tyr-158-COOH)] and One New δ Variant: Hb A2-North Africa [δ59(E3)Lys→Met]

We present here five new hemoglobin (Hb) variants which have been identified during routine Hb analysis before their genotypic characterization. Four of these result from a classical missense mutation: Hb Canuts [α85(F6)Asp→His (α1)], Hb Ambroise Pare [α117(GH5)Phe→Ile (α2)], Hb Beaujolais [β84(EF8)Thr→Asn] and HbA₂-North Africa [δ59(E3)Lys→Met]. The last one, Hb Monplaisir [β147 (Tyr-Lys-Leu-Ala-Phe-Phe-Leu-Leu-Ser-Asn-Phe-Tyr-158-COOH)], results from a frameshift mutation at the stop codon of the β-globin gene which leads to a modified C-terminal sequence in the β-globin chain. None of these variants seem to have a particular clinical expression in the heterozygous state. The circumstances of the discovery of these five new Hb variants emphasize the fact that an association of techniques is necessary for a complete screening of Hb variants during routine Hb analysis. Globin chain separation by reversed phase liquid chromatography (RP‐LC) appears to be the most relevant method.     

First detection of Hb Taybe [α38(C3) or α39(C4) Thr→0 (α1)] in an Italian child

Hb Taybe [α38(C3) or α39(C4) Thr→0 (α1)] is an unstable hemoglobin (Hb) variant caused by a deletion of a threonine residue at codon 39 of the α1-globin chain. Usually asymptomatic or with minimal hematological abnormalities in the heterozygous state, Hb Taybe becomes clinically evident in compound heterozygosity with α-thalassemia (α-thal) or in homozygous patients. To date, Hb Taybe has been described in Israeli-Arab and Greek individuals. We report, for the first time, a patient with chronic hemolytic anemia due to the presence of Hb Taybe in trans to the α2 initiation codon mutation ATG>ACG in an Italian child. Hb Taybe was not evident at Hb analysis with cellulose acetate electrophoresis and high performance liquid chromatography (HPLC). Globin biosynthetic studies revealed an α/β-globin ratio in the range of β-thal trait. Consequently, an investigation of the α- and β-globin genes was requested in order to avoid missing any rare globin chain variant and to offer accurate genetic counseling.     

The First Case of Hb Groene Hart [α119(H2)Pro→Ser,CCT→TCT (α1)] Homozygosity Confirms That a Thalassemia Phenotype Is Associated with this Abnormal Hemoglobin Variant

Hb Groene Hart [α119(H2)Pro→Ser, CCT→TCT (α1)] has been reported in heterozygotes of Moroccan origin and also in association with the common ?α^3.7 deletion. In all cases, the mutated protein was not detectable but was apparently associated with a mild α-thalassemia (thal) phenotype, presumably due to a modification of the α-globin chain domain that is recognized by the a hemoglobin stabilizing protein (AHSP). The present case of Hb Groene Hart homozygosity, confirms that the α-thal phenotype is associated with this α-globin chain. Hb Groene Hart must be quite frequent not only in Morocco but probably also among the northern African coastal population.     

Nondeletional Hb Queens Park [α32(B13)Met→Lys]/Hb H (β4) Disease

A rare nondeletional α-thalassemia-2 (α-thal-2) allele was identified in a Thai boy with Hb H (β4) disease. The proband has α-thal-1 (– –^SEA type) together with a non productive Hb Queens Park (HBA1:c.98T>A) [α32(B13)Met→Lys] α1-globin variant. No abnormal hemoglobin (Hb) fraction was detected by high performance liquid chromatography (HPLC). The clinical effect of this mutation in the proband was comparable to that of deletional α-thal-2 present in Hb H disease.     

Hb Beograd (α2β2 121 (GH4) Glu → Val) Observed In A New Yugoslavian Family

Hb Beograd was first discovered in a Yugoslavian family (1) while the same variant, under the name of Hb D Camperdown, was found in a Yugoslavian woman living in Australia (2). Recently, Wilkinson et al (3,4) reported two more Yugoslavian families with this variant. The present report describes the same variant in a new Yugoslavian family. The methodology used in these studies followed procedures routinely in use in our laboratories (5).     

Nondeletional Hb Queens Park [α32(B13)Met→Lys]/Hb H (β4) disease

A rare nondeletional α-thalassemia-2 (α-thal-2) allele was identified in a Thai boy with Hb H (β4) disease. The proband has α-thal-1 (- -(SEA) type) together with a non productive Hb Queens Park (HBA1:c.98T>A) [α32(B13)Met→Lys] α1-globin variant. No abnormal hemoglobin (Hb) fraction was detected by high performance liquid chromatography (HPLC). The clinical effect of this mutation in the proband was comparable to that of deletional α-thal-2 present in Hb H disease.     

A new α1-globin mutation, Hb Brugg [α20(B1)His→Gln

A 2?-year-old male child and a 23-year-old woman with no clinical symptoms were investigated during routine consultations. Cation exchange high performance liquid chromatography (HPLC) revealed an additional peak eluting before Hb A. DNA sequencing showed a novel heterozygous mutation at codon 20 of the α1-globin gene. The hemoglobin (Hb) variant was named Hb Brugg. Analysis of oxygen affinity Hb and Hb stability did not show any changes compared to normal Hb constellation.     

HB Melusine [α114(GH2)PRO→SER]: A New Neutral Hemoglobin Variant

Hb Melusine [α114(GH2)Pro→Ser] was found in an Algerian patient during a systematic screening for hemoglobinopathies performed in Luxembourg. The abnormal hemoglobin was suspected when a thickening of the Hb A band was observed by isoelectrofocusing. The mutant hemoglobin was silent in all other electrophoretic methods used for presumptive diagnosis with the exception of globin electrophoresis in the presence of Triton X-100. This technique revealed an α chain considerably more hydrophobic than normal. The structural abnormality of Hb Melusine concerns position α114(GH2) that belongs to a cluster of hydrophobic residues localized in the N-terminal half of the αT-12b tryptic peptide. It has been shown in the case of another variant of that position (Hb Nouakchott), that the replacement of the Pro GH2 by a Leu was responsible for a dramatic increase in the retention time of the a polypeptide chain during reversed phase high performance liquid chromatography, much higher than that reported for similar substitutions in other regions of the hemoglobin molecule.     

The Mutation of Hb Turriff [α99(G6)Lys→Glu (AAG→GAG)] Is Carried by the α1‐Globin Gene in a Japanese (Hb Turriff‐I)

The forms and severity of cardiac complications were investigated in patients with asymptomatic thalassemia intermedia and thalassemia major by M‐mode, bi‐dimensional echocardiography (ECHO) and echo‐Doppler. Twenty‐eight patients of both sexes with β‐thalassemia intermedia (β‐TI), mean age 23.2 ± 6.3 years, untransfused or minimally transfused, were compared to 42 age‐ and sex‐matched subjects with thalassemia major, who were regularly treated with hemotransfusive therapy [pre‐transfusion hemoglobin (Hb) values 9.5 ± 0.9 g/dL] and iron chelation. All patients were splenectomized. Age and sex matched healthy control subjects were randomly selected. β‐Thalassemia major (β‐TM) patients showed a marked reduction in contractile state and a milder left ventricular (LV) enlargement than β‐TI patients. Cardiac output (CO) and cardiac index (CI) were increased in both groups of patients but appeared significantly higher in β‐TI patients with consequent altered LV diastolic function indices. In addition, β‐TI patients had reduced indices of pulmonary artery flow related to long‐term chronic anemia rather than iron overload. The progressive rise in CO and CI casts doubts on the current management of β‐TI syndromes.     

Hb Paksé [(α2) CODON 142 (TA A→TA T OR Term→Tyr)] IN THAI PATIENTS WITH EABart's DISEASE AND Hb H DISEASE

Hb Paksé is caused by an α2-globin gene termination codon mutation, TA A→TA T or Term→Tyr, initially described in a Laotian family. We now report for the first time that the same mutation has been found in 14 Thai patients, seven with EABart's disease, four with Hb H disease, and three with α-thalassemia trait who were initially diagnosed as having Hb Constant Spring (Hb CS; α2-globin gene termination codon mutation T AA→C AA or Term→Gln). Co-inheritance of this mutation with α-thalassemia-1 (SEA type) leads to Hb H disease (hereafter designated as Hb H-Paksé disease) and to a complex thalassemia syndrome, namely EABart's-Paksé disease. Hematological data of these patients were compared with those of classical Hb H-CS and the EABart's patients. To facilitate epidemiological and diagnostic screening of Hb Paksé, a simple assay procedure based on allele specific polymerase chain reaction (PCR) amplifications was developed and validated. Using this allele specific PCR as a screening method, five additional individuals with Hb Paksé were found among 71 Thai subjects previously thought to have Hb CS.     

Hemoglobin Deer Lodge [α2β22(NA2)HIS→ARG] in a Venezuelan Family

The testing program of cord blood samples for hemoglobin (Hb) abnormalities, presently conducted in a few centers of Turkish Universities, sometimes detects rare variants which may or may not affect the health of the newborn. One example to be described here is O-Padova which has been observed once before (1). The variant was detected in the blood of a newborn girl by starch gel electrophoresis at pH 9.0 (2); the mobility of the variant (presumably _α2X_γ) was slightly slower than that of Hb C (or α₂β₂6 Glu→Lys) (Fig. 1). Red cell lysates from the father and a 2-year-old brother contained a different Hb component with a mobility distinctly faster than that of Hb A₂ or of Hb C; a minute quantity of a similar component (presumably α₂^X₂) was also present in the cord blood red cell lysate of Baby E (Fig. 1). The baby was retested when 40 days old; her hematological values and those of her father and brother were normal (Table I). Quantitation by cation exchange high performance liquid chromatography (HPLC) (3) gave total Hb X values of 15.4% for the baby (Hb X + Hb F_x), 18.3% for the father (Hb X + Hb X₂), and 12.8% for the brother (Hb X + Hb X₂) (see also Table I).     

Hb Jeddah [α68(E17)Asn→His (α1)]: A Newly Recognized α Chain Variant,Seen in Combination with Hb S [β6(A3)Glu→Val], and Found in Three Separate Families of Middle Eastern Origin

We report a previously unrecognized α chain variant identified in three families from Saudi Arabia, Yemen and Abu Dhabi. The index patient presented for hemoglobinopathy screening and was identified to have both this novel α chain variant and Hb S [β6(A3)Glu→Val, GAG→GTG]. Hb Jeddah results from a point mutation (AAC→CAC) at codon 68 in exon 2 of the α1 gene. There were no apparent hematological abnormalities or clinical symptoms in the three individuals identified as heterozygotes for Hb Jeddah, as well as the index case with both Hb S and Hb Jeddah. As we have found this variant in three separate families, the incidence may be greater than currently recognized.     

Hb J-Wenchang-Wuming [α11(A9)Lys→Gln (AAG>CAG) (α2 or α1)] compromises neonatal screening for α-thalassemia with the Sebia Capillarys2 electrophoresis system

We describe a Chinese newborn who was assumed to have α(0)-thalassemia (α(0)-thal) by determining the amount of Hb Bart's (γ4) in the cord blood, but was later shown to have only α(+)-thal. Hb J-Wenchang-Wuming [α11(A9)Lys→Gln (AAG>CAG) (α2 or α1)] was mistaken for Hb Bart's as both hemoglobin (Hb) variants have the same mobility.     

A Second Case of Hb Fontainebleau [α21(B2)Ala→Pro] in an Individual with Microcytosis

The identification of a second case of Hb Fontainbleau [α21(B2)Ala→Pro] allowed us to re‐examine its association with microcytosis, explore the effects of the mutation on protein stability and define the mutation at a DNA level. Although slightly unstable, the variant was expressed at 28–29% of the total and was caused by a heterozygous mutation in the α2 gene. There was no evidence for concomitant α-thalassemia (α-thal); both α-globin gene deletion analysis and sequencing of the α-globin locus failed to detect any additional mutations that might explain the relatively high expression level.     

Two new hemoglobin variants: Hb Aix-Les-Bains [β5(A2)Pro→Leu; HBB:c.17 C>T] and Hb Dubai [α122(H5)His→Leu (α2); HBA2:c.368 A>T

We report two new hemoglobin (Hb) variants; one causing an impairment of the N-terminal glycation of the β-globin chain and the other a hematological phenotype of α-thalassemia (α-thal). The first variant is Hb Aix-les-Bains [β5(A2)Pro→Leu] and the second Hb Dubai [α122(H5)His→Leu (α2)]. These two new Hb variants were detected by chromatographic and electrophoretic methods and characterized by molecular studies. Hb Dubai gives an α-thalassemic phenotype and should be routinely detected for preventing severe Hb H disease in couples at-risk for α-thal.