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beta-Thalassemia in Sicily: hematological and biosynthetic studies.

The degree of imbalance in beta(0)-Th and beta(+)-Th as well as the frequency of the two forms in Sicilian beta-thalassemic subjects have been studied. The hemoglobin synthesis in Rietti-Greppi-Micheli disease (RGMD) and in the beta-thalassemia trait has also been studied. In an unselected thalassemic population, about 30% have been found to be beta(0)-Th. Both groups of beta(0)-Th and beta(+)-Th showed severe imbalance with alpha/non-alpha ratio of 4.22 +/- 1.88 (SD) and 3.46 +/- 1.36, respectively. This difference was not statistically significant. In RGMD the alpha/non-alpha ratio was 2.12 +/- 0.36 while in the beta thalassemia trait it was 1.76 +/- 0.35.

Child

Screening coagulation tests and clotting factors in homozygous beta-thalassemia.

In 30 children with homozygous beta-thalassemia the hemostasis screening tests (bleeding time, PT, PTT), platelet count and specific assays of clotting factors were carried out 25 days after their last transfusion. PT, PTT, and bleeding time showed minor variations; considerable thrombocytosis was found in splenectomized patients. Factors IX and XII were decreased in a high proportion of patients, the vitamin K-dependent factors (II, VII, IX, X) were slightly reduced and factors I, V and VIII remained within the normal range in a majority of patients. Hepatic failure resulting in defective protein synthesis does not explain the more marked impairment of factors XI and XII, which might be secondary to activation of the intrinsic coagulation and/or kallikrein systems following intravascular haemolysis and multiple blood transfusions.

Adolescent

Human globin gene analysis for a patient with beta-o/delta beta-thalassemia.

Complementary DNA (cDNA) was prepared with RNA-dependent DNA polymerase from human globin messenger RNA (mRNA). Annealing and translation experimenta with total mRNA from circulating cells from a patient with heterozygous beta/heterozygous beta-delta-o thalassemia (beta-o/delta beta-o-thalassemia) demonstrated no detectable mRNA for beta-globin. cDNA enriched in sequences homologous to beta-globin mRNA was prepared by hydroxylapatite fractionation of hybrids formed between beta-o/delta beta-o-thalassemic mRNA and cDNA made from mRNA from a patient with alpha-thalassemia (hemoglobin H disease). The rate of annealing of this beta-enriched cDNA to normal human nuclear DNA was that of a sequence present as only a single copy per haploid genome. The beta-enriched cDNA annealed to the beta-o-delta beta-o-thalassemia total DNA with approximately the same kinetics as to normal DNA, indicating that no total gene deletion of beta-globin genes from the diploid genome has occurred, although the accuracy of the technique could not exclude with certainty a partial deletion or a deletion of a beta-globin gene from only one of the haploid genomes. This demonstrates that at least one of the beta-o- or the delta beta-o-thalassemia haploid genomes in this case contains a substantially intact beta-globin gene.

Adolescent

Genetic structure of the Greek gypsies.

Data are presented on several polymorphic genetic markers in 200 Greek gypsies. Polymorphic loci studied were: the ABO, MN, Rhesus, Kell and Duffy blood groups, hemoglobin, and ceruloplasmin. A survey for congenital malformations and hereditary diseases was also carried out on this group. The ABO, Rhesus, MN and Duffy system frequencies varied significantly from the figures obtained for the Greek population. However, there is a characteristic similarity between various gypsy groups studied in other nations and the distribution of polymorphic traits in the Punjab region of India. Cystic fibrosis, renal tubular acidosis, 21-hydroxylase deficiency, Hoty-Oram syndrome and homozygous beta-thalassemia were diagnosed within the gypsy group studied.

ABO Blood-Group System

Evaluation of a simplified microchromatographic technique for hemoglobin A2 determination.

The simplified Hb A2 determination based on microchromatography in Pasteur pipets filled with DEAE-cellulose with glycine-KCN-NaCl as developers [14] is compared with a reference Hb A2 determination procedure based on starch-block electrophoresis. The utility of microchromatography as a routine Hb A2 assay and as a screening method to detect beta-thalassemia trait carriers and patients with iron deficiency anemia was investigated. Day-to-day variation of a control hemolysate and the correlation between the values obtained with the two methods and between determinations in duplicate on the same sample are given. The mean values obtained with both methods for the different groups do not differ significantly but the standard deviations and the coefficients of variation observed by the microchromatography are generally higher. Microchromatography in Pasteur pipets tends to overestimate low and normal Hb A2 concentrations and to underestimate high Hb A2 concentrations. The results of microchromatography are more significant for the diagnosis when Hb A2 concentrations are expressed in weight hemoglobin per volume of blood and not in percentages. The microchromatographic procedure was recently marketed. The results obtained with the commercial columns were in good correlation with those obtained with starch-block electrophoresis, but commercial columns give a 18% overestimation of the Hb A2 concentrations.

Adult

Hematological and hemoglobin synthesis studies in a family with deltabeta-thalassemia trait.

A Basque Spanish family with heterozygous deltabeta-thalassemia is described. Patients with this anomaly usually present hematological findings observed in classical beta-thalassemia, but clinical conditions and unbalanced chain synthesis are less severe. Our propositus, however, presented clinical and biosynthetic data similar to those described in thalassemia intermedia. A family study was also performed.

Adolescent

Ultrastructural modulations of cell surface determinants in pathological processes.

A novel approach for the ultrastructural localization of surface sialic acids is presented. Membrane-bound sialyl residues are chemically modified in situ by the covalent attachment of biotinyl residues, the latter of which are subsequently localized by ferritin-conjugated avidin. In contrast to previous methods, which have been based on electrostatic interactions, the above method does not affect cell surface charge. Consequently, the macromolecular configuration of the labeled sialoglycoconjugates is preserved. The method has been found to be more accurate in the quantitative evaluation and the topographical localization of membrane-based sialic acids both in normal and pathologically induced surface modulations. Modulations in cell surface sialic acid content and/or distribution have been demonstrated in beta-thalassemia and transformed lymphoid cells, and the consequences of such alterations are discussed regarding destruction vs. escape from the immune surveillance system.

Animals

[Preferential synthesis of fetal hemoglobin in in vitro cultures of erythroid precursors from peripheral blood of healthy persons and those with hemoglobinopathies].

The synthesis of fetal hemoglobin was investigated in in vitro cultures of erythroid precursors isolated from peripheral blood of normal individuals, newborns and of subjects with different hemoglobinopathies. Synthesis of hemoglobin was assessed by 35s-methionine labeling of cultures and measurement of the radioactivity incorporated into the hemoglobins A2, A, F and S isolated by column chromatography on DE 52 cellulose. The erythroid precursors from most of the studied individuals cultured in in vitro system responded with synthesized an average of 15% of Hb F while cultures from newborns produced an average of 60% of Hb F in comparison of 73% of Hb F in peripheral blood of the same newborns. Erythroid precusors from subjects heterozygotes for beta-thalassemia, heterozygotes for HPFH, and homozygotes for Hb S produced an average of 20%, 43% and 30% of Hb F, respectively, in comparison of 7%, 14% and 9% of Hb F, respectively, present in the RBC of the same individuals. These data support the previously published results (6-11) that erythroid bursts in culture reactivate the structural genes for the gamma chain synthesis.

Anemia, Sickle Cell

Efficacy and safety of mitapivat in adults with transfusion-dependent α-thalassaemia or β-thalassaemia (ENERGIZE-T): a double-blind, randomised, multicentre, placebo-controlled, phase 3 trial.

BACKGROUND: The absence of disease-modifying therapies for patients with α-thalassaemia and oral disease-modifying therapies for patients with β-thalassaemia has been a substantial unmet need in these patients. We assessed the efficacy and safety of mitapivat, an oral allosteric activator of pyruvate kinase, in adults with transfusion-dependent thalassaemia. METHODS: ENERGIZE-T is a global, double-blind, randomised, placebo-controlled, phase 3 trial, conducted across 19 countries in North America, Europe, Asia-Pacific, South America, and the Middle East. Patients aged 18 years or older with transfusion-dependent α-thalassaemia or β-thalassaemia were randomly allocated (2:1) with a central interactive response technology system, stratified by geographical region and thalassaemia genotype, to receive 100 mg mitapivat or placebo orally twice a day for 48 weeks. The primary endpoint was transfusion reduction response (TRR), defined as a reduction of at least 50% in transfused red blood cell units with a reduction of at least two units in any consecutive 12-week period until week 48 compared with baseline. Efficacy was analysed in the full analysis set, comprising all randomly allocated patients. Type, severity, and relationship of adverse events and serious adverse events were assessed in patients who received at least one dose of study treatment. This study is registered with ClinicalTrials.gov (NCT04770779) and is active but not recruiting. FINDINGS: Between Nov 30, 2021 and May 2, 2023, 305 patients were screened, of whom 258 were randomly allocated (median age 33·5 years [IQR 27·0-44·0]; 136 [53%] female and 122 [47%] male participants). Of 258 patients allocated, 238 (92%) completed the double-blind treatment period. All patients were required to have a safety follow-up approximately 4 weeks after the final dose of study drug, regardless of completion of the double-blind period or continuation into the open-label extension period. In the full analysis set, TRRs occurred in 52 (30%) of 171 patients in the mitapivat group and 11 (13%) of 87 in the placebo group (adjusted difference 18 percentage points [95% CI 8-27]; two-sided p=0·0003). The safety analysis set comprised 172 patients in the mitapivat group (including one patient allocated to the placebo group who received one dose of mitapivat in error) and 85 in the placebo group. Adverse events were reported in 155 (90%) patients treated with mitapivat and 71 (84%) treated with placebo; the most common events with mitapivat were headache, upper respiratory tract infection, initial insomnia, diarrhoea, and fatigue. Serious adverse events were reported in 19 (11%) patients treated with mitapivat and 13 (15%) treated with placebo. Ten (6%) patients who received mitapivat and one (1%) who received placebo discontinued study treatment due to adverse events. No deaths were reported. INTERPRETATION: Mitapivat significantly reduced the transfusion burden and was generally well tolerated, showing a favourable benefit-risk profile. These findings support mitapivat as the first oral disease-modifying therapy for adults with transfusion-dependent α-thalassaemia or β-thalassaemia, providing a new treatment option to reduce transfusion burden in this patient population. FUNDING: Agios Pharmaceuticals, Inc.

Adult

Exa-cel in Children with Transfusion-Dependent β-Thalassemia or Sickle Cell Disease.

BACKGROUND: Exagamglogene autotemcel (exa-cel) is a cell therapy in which autologous CD34+ hematopoietic cells are engineered through ex vivo clustered regularly interspaced short palindromic repeats-Cas9 editing of the erythroid-specific enhancer region of BCL11A to express fetal hemoglobin. In phase 3 studies involving participants 12 to 35 years of age with sickle cell disease or transfusion-dependent β-thalassemia, exa-cel eliminated vaso-occlusive crises and the need for red-cell transfusions. METHODS: In two ongoing, phase 3, open-label, single-group studies, we evaluated exa-cel in children 5 to 11 years of age with transfusion-dependent β-thalassemia or sickle cell disease. Before exa-cel infusion, participants underwent myeloablative conditioning with pharmacokinetically dose-adjusted busulfan. The primary end points were transfusion independence for at least 12 consecutive months in children with transfusion-dependent β-thalassemia and freedom from severe vaso-occlusive crises for at least 12 consecutive months in children with sickle cell disease. RESULTS: A total of 15 children with transfusion-dependent β-thalassemia and 11 with sickle cell disease received exa-cel; median follow-up was 16.0 months (range, 2.2 to 32.1) and 16.9 months (range, 7.6 to 33.1), respectively. Of 8 children with transfusion-dependent β-thalassemia who were followed to at least 16 months, 8 were transfusion independent; the status of the remaining 7 was not yet evaluable. Of 8 children with sickle cell disease who were followed to at least 16 months, 8 were free of vaso-occlusive crises; the status of the remaining 3 was not yet evaluable. All the children had at least one grade 3 or 4 adverse event; 2 children with transfusion-dependent β-thalassemia had severe veno-occlusive liver disease that was assessed as being related to busulfan conditioning, 1 of whom died. CONCLUSIONS: Exa-cel therapy resulted in transfusion independence or freedom from severe vaso-occlusive crises in participants with transfusion-dependent β-thalassemia or sickle cell disease, respectively, who were followed for at least 16 months. All the participants had grade 3 or 4 adverse events. (Funded by Vertex Pharmaceuticals and CRISPR Therapeutics; CLIMB THAL-141 ClinicalTrials.gov number, NCT05356195; CLIMB SCD-151 ClinicalTrials.gov number, NCT05329649.).

Child

Compound Heterozygous Hemoglobin Minneapolis-Laos and Codon 41/42 (-TTCT) in a Thai Female Adult: A Case Report and Literature Review.

Thalassemia is a prevalent genetic disorder in Southeast Asia. The Hemoglobin Minneapolis-Laos variant is very rarely reported with only two previously published reports that profile a total of three patients. Here, we present the first reported case of compound heterozygous β zero (β0)-thalassemia and Hemoglobin Minneapolis-Laos in a 46-year-old Thai female. She presented at Siriraj Hospital (Bangkok, Thailand) with chronic microcytic anemia, which is a more severe phenotype than would be expected from either trait alone. Initial hemoglobin electrophoresis via high-performance liquid chromatography and capillary electrophoresis revealed elevated hemoglobin A2 (5.5% and 6.3%, respectively), which is a finding consistent with a β-thalassemia trait, but this finding failed to explain the full extent of her anemia. Next-generation sequencing was then performed to investigate for a congenital red blood cell disorder. The results identified the following two mutations in the β-globin gene (HBB): heterozygous β0-thalassemia codon 41/42 (-TTCT), and HBB c.356T >A, the latter of which is consistent with hemoglobin Minneapolis-Laos. This case highlights the importance of advanced genetic testing to diagnose rare hemoglobin variants that cannot be identified by conventional investigation and further contributes to our understanding of this rare combination's clinical phenotype.

Humans

Precision Medicine in Transfusion-Dependent and Non-Transfusion-Dependent β-Thalassemia: Toward Personalized Diagnosis and Therapy.

β-thalassemia comprises a clinically heterogeneous group of disorders in which anemia severity, transfusion exposure, iron loading, and organ complications vary widely among individuals. This structured narrative review summarizes practical applications of precision medicine in transfusion-dependent thalassemia (TDT) and non-transfusion-dependent thalassemia (NTDT), with explicit attention to which strategies apply to each clinical category. Literature indexed in PubMed and Scopus from 2000 to 2025 was reviewed using terms related to thalassemia, precision medicine, magnetic resonance imaging (MRI), chelation tailoring, next-generation sequencing (NGS), fetal hemoglobin (HbF) modifiers, luspatercept, mitapivat, hepcidin, gene therapy, gene editing, and artificial intelligence (AI). Evidence was synthesized descriptively because interventions, outcomes, and populations were heterogeneous, and no pooled meta-analysis was performed. In TDT, precision care is centered on individualized transfusion planning, extended red-cell antigen matching, MRI-guided cardiac and hepatic iron monitoring, organ-directed chelation intensification, and selection of disease-modifying or curative approaches. In NTDT, precision care emphasizes accurate phenotype classification, MRI liver iron concentration, because serum ferritin may underestimate iron burden, selective chelation, surveillance for NTDT-specific complications, and individualized use of agents that improve anemia. Personalized chelation should include deferiprone, either alone or in combination, when cardiac iron is increased. Comprehensive molecular diagnosis should include HBB together with HBA1 and HBA2 assessment, while secondary and tertiary modifiers help explain phenotypic variability and complication risk. Hepcidin and growth differentiation factor 15 (GDF-15) are discussed as investigational biomarkers; transferrin saturation is not recommended for routine iron-overload assessment in thalassemia. AI currently has its strongest role in screening and diagnosis, whereas risk-stratification models remain exploratory. Equitable implementation requires standardized TDT/NTDT pathways, regional MRI and genomics access, longitudinal registries, and multidisciplinary interpretation.

Humans

DNA methylation matters: methylation of the γ-globin (HBG) gene promoters is required for postnatal silencing of HbF.

Sufficient levels of fetal hemoglobin (HbF) can ameliorate the pathophysiologic basis of sickle cell disease and β-thalassemia postnatally. DNA methylation has long been posited to mediate silencing of HbF expression, but this has been controversial. Recent publications provide definitive evidence for the critical role of HBG gene promoter methylation in silencing and insight into the mechanisms involved. The data support a model in which methylation of CpG sites in the HBG promoters and repressive transcription factors recruit the MBD2-NuRD chromatin remodeling complex, which enforces silencing. These findings have implications for the treatment of β-globin disorders.

DNA Methylation

Clinical efficacy of thalidomide for various genotypes of beta thalassemia.

OBJECTIVE: The objective of this study was to investigate the therapeutic efficacy of thalidomide across various genotype presentations of &#x3b2;-thalassemia so as to facilitate the early screening of thalidomide-sensitive thalassemia cases and to understand the impact of iron overload on thalidomide. METHODS: From our initial sample of 52 patients, we observed 48 patients with &#x3b2;-thalassemia for two years after administration of thalidomide. This cohort included 34 patients with transfusion-dependent thalassemia (TDT) and 14 patients with non-transfusion-dependent thalassemia (NTDT). We recorded the values of hemoglobin (Hb), fetal hemoglobin (HbF), and serum ferritin (SF) in the baseline period and at 1, 3, 6, 12, 18, and 24 months after enrollment, as well as the pre- and post-treatment blood transfusion volume in all 48 cases. According to the increase in Hb levels from baseline during the 6-month observation period, the response to thalidomide was divided into four levels: main response (MaR), minor response (MiR), slow response (SLR), and no response (NR). A decrease in serum ferritin levels compared to baseline was considered alleviation of iron overload. We calculated the overall response rate (ORR) as follows: ORR&#x2009;=&#x2009;MaR&#x2009;+&#x2009;MiR&#x2009;+&#x2009;SLR/number of observed cases. RESULTS: The ORR was 91.7% (44/48 cases), and 72.9% showed MaR (35/48 cases). Among the 34 patients with TDT, 21 patients (61.8%) were free of blood transfusion, and the remaining 13 patients still required blood transfusion, but their total blood transfusion volume reduced by 31.3% when compared to the baseline. We found a total of 33 cases with 10 combinations of advantageous genes, which included 5 cases with &#x3b2;CD41-42/&#x3b2;CD17 and 6 cases with &#x3b2;CD41-42/&#x3b2;-28. Based on the treatment outcomes among the 48 cases in the observation group, there were 33 cases in the MaR group and 15 cases in the SLR/NR group. There was a difference in HbF between the two groups at baseline (P&#x2009;=&#x2009;0.041). There were significant differences between the two groups in Hb and HbF at the time points of 6 and 12 months, respectively (P&#x2009;<&#x2009;0.001). Compared to the baseline measurement, there was a significant decrease in the level of SF at months 12 and 24 (P&#x2009;<&#x2009;0.001). CONCLUSION: In this study, we identified 10 &#x3b2;-thalassemia gene combinations that were sensitive to thalidomide. These gene combinations can be used for initial screening and to predict the therapeutic effect of thalidomide in clinical practice. We examined the therapeutic response to thalidomide and found that the administration of thalidomide in combination with standardized iron removal was more beneficial in reducing iron overload.

Humans