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At least 19 recordsLinked to original sources
PubMed1975

A new Hb variant: Hb F Sardinia gamma75(E19) isoleucine leads to threonine found in a family with Hb G Philadelphia, beta-chain deficiency and a Lepore-like haemoglobin indistinguishable from Hb A2.

A 59-year-old man with beta-thalassaemia major is unusually well. He has no beta-chains in his haemoglobin but is heterozygous for the genes responsible for alphaA and for alphaG Philadelphia. In addition he is also heterozygous for the genes responsible for gammaF and a new gamma-chain, gamma75(E19) Ile-Thr, named gammaF Sardinia. It was not possible to isolate the mutant gamma-chain, but from the overall ratios of Ggamma-:Agamma-Chain and gamma75 Ile : gamma75 Thr, it could be inferred that the mutation had presumably occured in the Ggamma-chain. Some of the propositus' siblings have high levels of Hb A2, and it is suggested that they possibly carry a gene for Lepore chain with the deltabeta-crossover after residue delta126.

Chromatography, Paper↗
PubMed1977

Detection and quantitation of the fetal hemoglobin variant Hb F-Malta-I in adults.

A variant of fetal hemoglobin (Hb F-Malta-I) has been detected and quantitated in adult blood with a sensitive radioimmunoassay employing monospecific antisera. The concentration of Hb-F-Malta-I was 0.002-0.05%, with an average value of 0.011%. The ratio of Hb F-Malta-I/Hb F in adults was about 4.8%, compared to a ratio of about 27% in the newborn. Since the F-Malta-I variant is a product of a mutated Ggamma locus, which is one of the nonallelic structural genes directing the gamma chain synthesis, its presence in blood of adults shows that the synthesis of this gene is not completely suppressed after birth, as was previously suggested.

Adult↗
PubMed1978

A new hemoglobin variant. HB Yatsushiro alpha 2 A beta 2 60 Val replaced by Leu.

This study was performed to establish the structural abnormality of a new hemoglobin variant discover-d in a Japanese patient with angina pectoris. The hybridization of the separated hemoglobin with canine hemoglobin revealed a beta-chain anomaly. Peptide betaTp-6 was found to be abnormally located on the peptide map of tryptic digests of the S-carboxymethylated beta-chain from the variant hemoglobin. A structural study on the abnormal betaTp-6 revealed that the variant hemoglobin differs from hemoglobin A by substitution of leucine for valine at residue 60 of the beta-chain. This new variant hemoglobin is designated as hemoglobin Yatsushiro after the name of the city where the propositus lived. The patient is hematologically healthy and his clinical history has nothing to do with this abnormal hemoglobin.

Genetic Code↗
PubMed1978

Variability in the interaction of beta-thalassemia with the alpha-chain variants Hb G-Philadelphia and Hb Rampa.

Two unrelated families are reported in which beta-thalassemia trait occurred with a heterozygosity of Hb G-Philadelphia (alpha2 68(E17)Asn leads to Lys beta2) in one family and with Hb Rampa (alpha2 95(G2)Pro leads to Ser beta2) in the other. The percentage of Hb G-Philadelphia was not influenced by the simultaneous presence of a beta-thalassemai determinant, but that of Hb Rampa was descreased from 20% in the simple heterozygote to about 6% in persons with the Hb Rampa-beta-thalassemia combination. Data from in vitro recombination experiments with isolated alpha X, alpha A, and beta A chains, with heme attached, indicated a preferential formation of Hb A over Hb Rampa but not over Hb G-Philadelphia in conditions of relative beta-chain deficiency. This suggests that the rate of assembly of monomers to form dimers or tetramers can be an important mechanism of controlling the quantity of certain hemoglobin variants with critical substitutions in heterozygotes.

Adolescent↗
PubMed1979

Hemoglobin G San José [beta 2 7 (A4) Glu to Gly alpha 2], beta thalassemia, and alpha thalassemia in a Sicilian family.

A 3-year-old child of Sicilian origin was found to have a severe form of Cooley's anemia. Investigations were extended to other members of her family. In three, a rare beta-chain structural Hb variant, Hb G San José [beta 7 (A4) Glu to Gly], was observed: in the father of the porposita heterozygosity for the abnormal Hb was found to be coexistent with beta o thalassemia; two sisters had lowered MCV and MCH values and levels of the abnormal Hb significantly lower than in other heterozygotes for Hb G San José. The alpha-chain/total beta-chain synthesis ratios suggest an alpha-thalassemic-like effect. Their mother had lowered MCV and MCH values, an Hb A2 level in the upper limit of the normal range, and a balanced alpha-chain/beta-chain synthesis ratio. Therefore, the possibility of coexistence of an alpha thalassemia trait with a beta thalassemia trait in the mother of the proposita and with Hb G San José heterozygosity in the two sisters who had lowered levels of abnormal Hb is discussed.

Child, Preschool↗
PubMed2024

Application of third-generation sequencing technology for identifying rare α- and β-globin gene variants in a Southeast Chinese region.

BACKGROUND: Third-generation sequencing (TGS) based on long-read technology has been gradually used in identifying thalassemia and hemoglobin (Hb) variants. The aim of the present study was to explore genotype varieties of thalassemia and Hb variants in Quanzhou region of Southeast China by TGS. METHODS: Included in this study were 6,174 subjects with thalassemia traits from Quanzhou region of Southeast China. All of them underwent common thalassemia gene testing using the DNA reverse dot-blot hybridization technology. Subjects who were suspected as rare thalassemia carriers were further subjected to TGS to identify rare or novel α- and β-globin gene variants, and the results were verified by Sanger sequencing and/or gap PCR. RESULTS: Of the 6,174 included subjects, 2,390 (38.71%) were identified as α- and β-globin gene mutation carriers, including 40 carrying rare or novel α- and β-thalassemia mutations. The αCD30(-GAG)α and Hb Lepore-Boston-Washington were first reported in Fujian province Southeast China. Moreover, the βCD15(TGG> TAG), βIVS-II-761, β0-Filipino(~ 45 kb deletion), and Hb Lepore-Quanzhou were first identified in the Chinese population. In addition, 35 cases of Hb variants were detected, the rare Hb variants of Hb Jilin and Hb Beijing were first reported in Fujian province of China. Among them, one case with compound αααanti3.7 and Hb G-Honolulu variants was identified in this study. CONCLUSION: Our findings may provide valuable data for enriching the spectrum of thalassemia and highlight the clinical application value of TGS-based α- and β-globin genetic testing.

Humans↗
PubMed1975

A double heterozygous hemoglobin. Hemoglobin OIndonesia and hemoglobin DPunjab in an individual.

During surveys for abnormal hemoglobins in Iran, an individual was found to have four electrophoretically distinct hemoglobins. The abnormality was found only in the father of the propositus, in two of the father's sisters, and in three brothers and sisters of the propositus. Investigations revealed that the four hemoglobin components are the result of a double heterozygosity between an alpha-chain variant (Hb OIndonesia) and a beta-chain variant (Hb DPunjab). The presence of the abnormal hemoglobins was not associated with hemolytic disorders or obvious clinical symptoms.

Blood Protein Electrophoresis↗
PubMed1975

Hemoglobin Koya Dora: high frequency of a chain termination mutant.

Approximately 10% of the members of the Koya Dora tribe from Andhra Pradesh (India) carry an alpha chain hemoglobin variant, Hb Koya Dora (Hb KD), usually in amounts of 0.5%-2% of total hemoglobin. In four presumed homozygotes for Hb KD, up to 10% of the abnormal hemoglobin was present. The alpha chain of Hb KD was found to be elongated by at least 16 residues, possibly as a result of a mutation of the normal alpha chain termination codon UAA TO UCA, coding for serine. A pedigree in which two individuals possess Hb KD as well as the alpha chain variant Hb Rampa and normal Hb A proves the existence of two alpha chain loci in this population. Hb DK resembles the previously described Hb Constant Spring [6, 7] in many aspects, probably also in its alpha thalassemia-like expression.

Amino Acids↗
PubMed1978

Beta-chain variants in Jamaican newborns.

In an electrophoretic study of 15,661 Jamaican cord bloods, 8 rare beta-chain variants were found in 18 subjects in addition to the common beta-chain variants, Hb S and Hb C. The heterozygote frequencies for Hb S and Hb C were 10.1% and 3.7% respectively. The most frequent of the rare beta-chain variants were Hb Korle Bu (beta 73 Asp leads to Asn) (7 cases) and Hb O su-Christiansborg (beta 52 Asp leads to Asn) (3 cases). One new beta-chain variant, Hb Caribbean (beta 91 Leu leads to Arg) was found.

Chromatography, Ion Exchange↗
PubMed1978

Hemoglobin Legnano (alpha2 141 (HC3) Arg replaced by Leu beta2): a new abnormal human hemoglobin with high oxygen affinity.

An abnormal, fast moving hemoglobin was noted in a 34-yr-old male patient living in Legnano (northern Italy) affected with renal failure and iron deficiency anemia, not related to the presence of the Hb variant. Structural studies have demonstrated a previously undescribed amino acid substitution, alpha 141 Arg replaced by Leu. This new variant has been named Hb Legnano, and is characterized by an increased oxygen affinity and a low cooperativity, at least as far as preliminary functional studies carried out on whole blood have indicated. Family studies are reported: three other heterozygous carriers were observed among the relatives of the propositus, all showing a mild polycythemia which, however, does not seem to produce appreciable clinical consequences.

Adult↗
PubMed1975

Hb Camden and Hb Hope found during routine testing.

The electrophoretically fast-moving hemoglobin variant Hb Camden [beta131 (H9) gln leads to glu] has been found in a middle-aged female suffering from pulmonary disease, and Hb Hope [beta136 (H14) gly leads to asp] which migrates just ahead and very close to Hb A was present in a young obstetrical patient with a mild hemolytic anemia.

Adult↗
PubMed1976

Hemoglobin J Cairo: beta 65 (E9) Lys leads to Gln, A new hemoglobin variant discovered in an Egyptian family.

The present report describes clinical, hematological and biochemical studies of a 27-year old Egyptian woman in whom a fast moving Hb variant was found. The abnormal Hb constituted 48% of the total erythrocyte Hb of the propositus and her father. Structural studies demonstrated that in the abnormal Hb lysine beta 65 is replaced by glutamine. The new Hb mutant is designated hemoglobin J Cairo beta 65 (E9) Lys leads to Gln. This substitution results in only a moderate decrease in cooperativity. No evidence of Hb instability was found. A slight anemic state has been observed in the propositus since she reached adolescence.

Adult↗
PubMed1978

Unbalanced globin chain synthesis by Hb Lincoln Park (anti-Lepore) reticulocytes.

Hemoglobin synthesis was studied in vitro in reticulocytes from a patient with the anti-Lepore variant Hb Lincoln Park. Incorporation of L-leucine-3H into the alpha and beta delta chains of Hb Lincoln Park was substantially less than the incorporation into the corresponding globin chains of Hb A, with the rate of synthesis of the beta delta chain being similar to that of the delta chain of Hb A2. Synthesis of the alpha and total non-alpha globin components was unbalanced, with a substantial excess of alpha chain synthesis. These findings help to explain the mild hemolytic disease present in individuals with this hemoglobin variant.

Globins↗
PubMed1978

Is the trimodality of Hb Leslie (alpha 2 beta 2 131 Gln---O) in heterozygotes the result of a variable number of active alpha-chain genes? Evidence for posttranslational control of hemoglobin synthesis.

Whether the trimodality in the relative concentration of the hemoglobin variant Hb Leslie in heterozygotes (Huisman, Hemoglobin 1:349-382, 1977) is due to a polymorphism of the alpha-chain structural genes was investigated by conventional incubation of reticulocytes with 14C-leucine. In addition, an aliquot from each of the incubations was incubated under the same conditions but without isotope. Three Hb Leslie heterozygotes with presumably four, three (heterozygous alpha-thalassemia-2), and two (homozygous alpha-thalassemia-2) active alpha-chain genes and with 33%, 22% and 11% Hb Leslie respectively, and one patient with the Hb Leslie beta(0)-thalassemia condition with more than 85% Hb Leslie were studied. The data indicate that betaLeslie chains have a lower affinity for alpha chains that betaA chains. A concomitant alpha-chain deficiency results in a reduced incorporation of betaLeslie chains into the tetrameric Hb Leslie molecules, while the quantity of Hb Leslie produced correlates with the degree of alpha-chain deficiency. Excess of betaLeslie chains is preferentially degraded.

Female↗
PubMed1978

An unstable haemoglobin, Hb Tacoma beta30 (B12) arg leads to ser, detected at birth by the demonstration of red cell inclusions.

Incomplete expression of human haemoglobin beta-chains at birth may lead to difficulty in the early demonstration of an inherited beta-chain variant. In this case, the rare unstable variant, Hb Tacoma beta30 (B12) arg leads to ser, although not present in cord blood in sufficient amounts to be easily detected by routine electrophoretic techniques, was readily shown to be present by the striking inclusions provoked by prolonged incubation of the neonatal red cells with new methylene blue.

Adult↗
PubMed1979

Structural bases of the inhibitory effects of hemoglobin F and hemoglobin A2 on the polymerization of hemoglobin S.

We have previously found that the inhibitory effect of hemoglobin F (Hb F) on the polymerization of Hb S proceeds via the formation of asymmetrical hybrid tetramers of the type alpha2betasgamma. Examination of the gelling properties of binary mixtures of Hb S and several Hb variants now shows that, among the gamma chain amino acid residues that differ from those of the beta chain, residues gamma80 (EF4) and gamma87 (F3) are at least partly responsible for this inhibition. Furthermore, we find that mixing Hb A2(alpha2delta2) with Hb S strongly inhibits gelling to an extent similar to that seen with Hb S/Hb F mixtures; this inhibition is attributable to amino acid differences between the delta and beta chain sequences at positions delta22 (B4) and delta87 (F3). Therefore, residues 22, 80, and 87 of the beta chain appear to be involved in intermolecular contact sites that stabilize the deoxy Hb S polymers.

Amino Acid Sequence↗
PubMed1977

Hemoglobin Pontoise alpha63 Ala replaced by Asp(E12). A new fast moving variant.

The present report describes structural and functional studies of a new hemoglobin variant, Hb J Pontoise. This abnormal hemoglobin was discovered in a 36 year old Spanish man. The substitution of alpha63 (E12) Ala replaced by Asp is situated at an external site and appears to have no influence on the function of the hemoglobin. Nevertheless, it presents some instability in vitro, as demonstrated by the isopropanol test. This instability could partially explain the low percentage of the abnormal hemoglobin in the hemolysate (12%), since its rate of synthesis was normal.

Adult↗