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3.
Br J Haematol ; 204(5): 2025-2039, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38613149

RESUMEN

Splenectomised ß-thalassaemia/haemoglobin E (HbE) patients have increased levels of circulating microparticles or medium extra-cellular vesicles (mEVs). The splenectomised mEVs play important roles in thromboembolic complications in patients since they can induce platelet activation and endothelial cell dysfunction. However, a comprehensive understanding of the mechanism of mEV generation in thalassaemia disease has still not been reached. Thalassaemic mEVs are hypothesised to be generated from cellular oxidative stress in red blood cells (RBCs) and platelets. Therefore, a proteomic analysis of mEVs from splenectomised and non-splenectomised ß-thalassaemia/HbE patients was performed by liquid chromatography with tandem mass spectrometry. A total of 171 proteins were identified among mEVs. Interestingly, 72 proteins were uniquely found in splenectomised mEVs including immunoglobulin subunits and cytoskeleton proteins. Immunoglobulin G (IgG)-bearing mEVs in splenectomised patients were significantly increased. Furthermore, complement C1q was detected in both mEVs with IgG binding and mEVs without IgG binding. Interestingly, the percentage of mEVs generated from RBCs with IgG binding was approximately 15-20 times higher than the percentage of RBCs binding with IgG. This suggested that the vesiculation of thalassaemia mEVs could be a mechanism of RBCs to eliminate membrane patches harbouring immune complex and may consequently prevent cells from phagocytosis and lysis.


Asunto(s)
Hemoglobina E , Proteómica , Talasemia beta , Humanos , Talasemia beta/sangre , Talasemia beta/metabolismo , Hemoglobina E/metabolismo , Proteómica/métodos , Femenino , Masculino , Adulto , Vesículas Extracelulares/metabolismo , Esplenectomía , Inmunoglobulina G/sangre , Membrana Eritrocítica/metabolismo , Proteoma/análisis , Adolescente , Eritrocitos/metabolismo , Micropartículas Derivadas de Células/metabolismo , Adulto Joven
5.
Int J Gynaecol Obstet ; 166(1): 360-367, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38234105

RESUMEN

OBJECTIVE: To compare obstetric outcomes between women with ß-thalassemia/hemoglobin E (ß-thal/HbE) disease and those of low-risk pregnancies, and also between the two subgroups, ß-thal0/HbE and ß-thal+/HbE disease. METHODS: A retrospective cohort study was undertaken on pregnant women with ß-thal/HbE disease and low-risk pregnancies, which were randomly selected with a case-to-control ratio of 1:10. RESULTS: Pregnancies with ß-thal/HbE disease were identified in 0.19% of 59 152 pregnancies, including 104 women in the study group and 1040 women in the control group. The mean gestational age and mean birth weight were significantly lower in the study group. The prevalence of fetal growth restriction, preterm birth and low birth weight were significantly increased in the study group based on both univariate and multivariate analysis. The impacts were more striking in the ß-thal0/HbE subgroup than in the ß-thal+/HbE subgroup. The cesarean rate was significantly higher in the study group. No maternal death or serious complication was found in this cohort. CONCLUSION: Based on this cohort, the largest ever published, ß-thal/HbE disease is significantly associated with increased incidence of fetal growth restriction, preterm birth and low birth weight. The impacts were more pronounced in the ß-thal0/HbE subgroup. Pregnancy may be relatively safer for women with ß-thal/HbE disease.


Asunto(s)
Retardo del Crecimiento Fetal , Hemoglobina E , Recién Nacido de Bajo Peso , Resultado del Embarazo , Nacimiento Prematuro , Talasemia beta , Humanos , Femenino , Embarazo , Estudios Retrospectivos , Talasemia beta/epidemiología , Talasemia beta/complicaciones , Adulto , Resultado del Embarazo/epidemiología , Nacimiento Prematuro/epidemiología , Recién Nacido , Retardo del Crecimiento Fetal/epidemiología , Complicaciones Hematológicas del Embarazo/epidemiología , Estudios de Casos y Controles , Edad Gestacional , Cesárea/estadística & datos numéricos , Peso al Nacer , Adulto Joven
6.
Lab Med ; 55(4): 528-533, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38253465

RESUMEN

We present 3 cases of discordant results from screening hemoglobin A1c (HbA1c) measured by ion-exchange high-performance liquid chromatography (HPLC) all due to various forms of interference and flagged by the instrument as "suspected hemoglobin E (HbE)." The first case was due to a rare hemoglobin variant, later confirmed to be hemoglobin Hoshida, the second due to "true" heterozygous HbE, and the third a result of analytical artifact causing splitting of the HbA1c peak without an underlying variant hemoglobin. We examine the similarities in these cases along with the laboratory work-up to classify each cause of interference to demonstrate the wide array of potential causes for the suspected HbE flag and why it warrants proper work-up. Because there is no standardized method of reporting out hemoglobin variant interference in HbA1c measurement, we discuss our laboratory's process of investigating discordant HbA1c measurements and reporting results in cases with variant interference as 1 possible model to follow, along with discussing the associated laboratory, ethical, and clinical considerations. We also examine the structure of hemoglobin Hoshida, HbE, and conduct a brief literature review of previous reports.


Asunto(s)
Hemoglobina Glucada , Hemoglobina E , Humanos , Hemoglobina Glucada/análisis , Cromatografía Líquida de Alta Presión/métodos , Cromatografía por Intercambio Iónico/métodos , Hemoglobina E/análisis , Hemoglobina E/genética , Masculino , Femenino , Persona de Mediana Edad , Adulto
7.
Hemoglobin ; 48(1): 1-3, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38258429

RESUMEN

A 21-year-old patient presented with a previous medical history of pallor, mild icterus, increased fatigue, low hemoglobin, and abnormal hemoglobin variant analysis with more than 70 transfusions. He was referred for genetic analysis to identify the pathogenic variations in the ß-globin gene. Sanger's sequencing of the proband and his family revealed the presence of a novel frame shift variant HBB:c.163delG in a compound heterozygous state with hemoglobin E (HbE) (HBB:c.79G > A) variant. The father and the sibling of the patient were found to be normal for the HBB gene. Mother was found to be heterozygous for HbE (HBB:c.79G > A) variant. In silico analysis by Mutalyzer predicted that c.163delG variant generated a premature stop codon after seven codons, leading to a truncated protein. FoldX protein stability analysis showed a positive ΔΔG value of 45.27 kcal/mol suggesting a decrease in protein stability. HBB:c.79G > A is a known variant coding for HbE variant, which results in the reduced synthesis of ß-globin chain and shows mild thalassemia. Combined effect of HBB:c.163delG and HBB:c.79G > A variants in the proband might have led to the reduced synthesis of ß-globin chains resulting in a thalassemia intermedia type of clinical manifestation.


Asunto(s)
Hemoglobina E , Hemoglobinas Anormales , Talasemia beta , Humanos , Masculino , Adulto Joven , Globinas beta/genética , Globinas beta/metabolismo , Talasemia beta/diagnóstico , Talasemia beta/genética , Hemoglobina E/genética , Hemoglobinas Anormales/genética , Heterocigoto , Mutación , Fenotipo
8.
Clin Chem Lab Med ; 62(7): 1383-1392, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38197862

RESUMEN

OBJECTIVES: Hemoglobinopathies, including thalassemia and hemoglobin (Hb) variants, are common hematological disorders in tropical countries. Accurate and precise separation of hemoglobin types and reliable quantitation are necessary for differential diagnosis of these disorders. METHODS: We have evaluated the analytical performances of premier resolution-high-performance liquid chromatography (PR-HPLC; Trinity Biotech, Co. Wicklow, Ireland) to assist in the presumptive diagnosis of thalassemia and Hb variants commonly found in Southeast Asian countries. HbA0, HbA2, HbE, and HbF levels were separated and quantified in 120 blood samples from unrelated adult subjects and compared with those analyzed by capillary zone electrophoresis (CZE; CAPILLARYS™ 2, Sebia, Norcross, GA, US). The Hb analysis patterns of Hb variants obtained from the PR-HPLC system were also compared to those obtained from HPLC (VARIANT II, ß-thalassemia Short Program, Bio-Rad, Laboratories, Hercules, CA, US) and CZE systems. RESULTS: The PR-HPLC had excellent precision with a coefficient of variation (CV) for HbA2 quantitation of 3.8 % within-run and 5.2 % between-run. The levels of HbA2/E quantified by the PR-HPLC system correlated well with those of the CZE system (r=0.997). In addition, thalassemia interpretation results obtained from the PR-HPLC and the CZE showed 100 % agreement. Moreover, chromatograms of the PR-HPLC were also comparable to those of VII-HPLC and CAP2-CZE electropherograms. CONCLUSIONS: The PR-HPLC system would be applicable to diagnose common forms of thalassemia and Hb variants in Southeast Asia.


Asunto(s)
Electroforesis Capilar , Humanos , Cromatografía Líquida de Alta Presión/métodos , Electroforesis Capilar/métodos , Hemoglobinas Anormales/análisis , Hemoglobina A2/análisis , Hemoglobina E/análisis , Hemoglobinopatías/diagnóstico , Hemoglobinopatías/sangre , Hemoglobina Fetal/análisis , Adulto
9.
J Clin Endocrinol Metab ; 109(2): e562-e568, 2024 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-37772731

RESUMEN

BACKGROUND: Adrenal insufficiency (AI) in hemoglobin E (HbE)/beta thalassemia, including evaluation of mineralocorticoid axis, had not been studied. AIMS AND OBJECTIVES: In this study, we attempted to evaluate the prevalence of AI in HbE/beta thalassemia and wanted to determine if the prevalence of AI varied according to severity of HbE/beta thalassemia and transfusion requirements. METHODS: In this observational, cross-sectional study, 104 patients with HbE/beta thalassemia were evaluated. Among them, 57 and 47 were transfusion dependent and non-transfusion dependent. According to Mahidol criteria, patients were classified into mild (n = 39), moderate (n = 39), and severe (n = 26) disease. Early morning (8 Am) serum cortisol, plasma ACTH, and plasma aldosterone, renin were measured. Patients with baseline cortisol of 5 to 18 µg/dL underwent both 1 µg and 250 µg short Synacthen test. According to these results, patients were classified as having either normal, subclinical, or overt (primary/secondary) adrenal dysfunction. RESULTS: Adrenal insufficiency was found in 41% (n = 43). Among them 83.7% (n = 34) had primary AI and 16.3% (n = 9) had secondary AI. Thirty-three patients (31%) with normal or elevated ACTH and with low or normal aldosterone with high renin were diagnosed as having subclinical AI. There was no difference in prevalence of AI between transfusion dependent and non-transfusion dependent (P = .56) nor was there was any difference in prevalence of AI according to disease severity (P = .52). CONCLUSION: Adrenal insufficiency is common in HbE/beta thalassemia and is independent of transfusion dependency and disease severity.


Asunto(s)
Insuficiencia Suprarrenal , Hemoglobina E , Talasemia beta , Humanos , Hidrocortisona , Talasemia beta/complicaciones , Talasemia beta/epidemiología , Talasemia beta/terapia , Aldosterona , Estudios Transversales , Renina , Hormona Adrenocorticotrópica , Insuficiencia Suprarrenal/diagnóstico , Insuficiencia Suprarrenal/epidemiología , Insuficiencia Suprarrenal/etiología
10.
J Pak Med Assoc ; 73(12): 2357-2362, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38083912

RESUMEN

OBJECTIVE: To detect mutation in cases having haemoglobin A2 level >7% on high performance liquid chromatography. METHODS: The cross-sectional, descriptive study was conducted from July 2017 to December 2018 at the Department of Haematology and Human Genetics and Molecular Biology, University of Health Sciences, Lahore, Pakistan, and comprised patients of either gender with haemoglobin A2 ≥7%. The samples were collected from different cities of Punjab in collaboration with the Punjab Thalassemia Prevention Programme, Lahore. The samples were subjected to complete blood count and high performance liquid chromatography using automated haematology analysers and variant-II beta thalassemia short programme, respectively. To analyse haemoglobin E mutations at the molecular level, polymerase chain reaction-restriction fragment length polymorphism (PCR_RFLP) was performed using a type IIS restriction endonuclease known as Mnl1 (derived from Moraxella nonliquefaciens) to cleave DNA at specific sites and the results were further confirmed on randomly selected samples using Sanger sequencing. Data was analysed using SPSS 25. RESULTS: Of the 39 patients, 15(38.5%) were males and 24(61.5%) were females. The overall median age was 14 (23) years. There were 29 (74.4%) patients with thalassemia family history, and 22(56.4%) had a positive family history of transfusion related to thalassemia, while no patient had a family history of iron therapy. The median haemoglobin A, haemoglobin A2 and haemoglobin F levels were 72.2 (65.2-79.1) %, 26.6 (19.1-34.0) % and 0.9 (-0.8-2.6) %, respectively. After molecular investigation, HbAE mutation was found in 23(59%) patients, while wild type HbAA genotype was found in 16(41%). The heterozygous HbE mutation was present in 23(59%) patients. CONCLUSIONS: Frequently missed/undiagnosed cases of haemoglobin E that co-elute with haemoglobin A2 in the same high performance liquid chromatography window were detected among those with haemoglobin A2 ≥7%.


Asunto(s)
Hemoglobina E , Talasemia , Talasemia beta , Masculino , Femenino , Humanos , Adolescente , Hemoglobina E/genética , Hemoglobina E/análisis , Hemoglobina A2/análisis , Hemoglobina A2/genética , Estudios Transversales , Genotipo , Talasemia beta/epidemiología , Talasemia beta/genética , Mutación
11.
Ann Med ; 55(2): 2264174, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37796611

RESUMEN

BACKGROUND: An increasing number of α-hemoglobin (Hb) variants is causing various clinical symptoms; therefore, accurate identification of these Hb variants is important. OBJECTIVE: This study aimed to describe the molecular and hematological characteristics of novel Hb Doi-Saket that gives rise to a typical α+-thalassemia phenotype in carriers with and without other hemoglobinopathies. MATERIALS AND METHODS: Biological samples from a proband and his family members were analyzed. Hematological profiles were analyzed using a standard automated cell counter. Hb was analyzed by capillary electrophoresis and high-performance liquid chromatography. Mutations and globin haplotype were identified by DNA analysis. Novel diagnostic tools based on allele-specific polymerase chain reaction (PCR) and PCR-restriction fragment length polymorphism were developed. RESULTS: Hb analysis showed a major abnormal Hb fraction, moving slower than HbA, and a minor Hb fraction alongside HbA2 in the proband, his father, and son. DNA analysis of the α-globin gene identified the -α3.7 deletion and in cis the C > A mutation on codon 9 of the α2α1 gene, corresponding to Hb Doi-Saket [α9(A7) Asn > Lys]. This mutation could be identified using newly developed allele-specific PCR-based assays. The Hb Doi-Saket al.lele was significantly associated with haplotype [- + M + + 0 -]. Interaction of αDoi-Saket with ßE globin chains led to a new Hb variant (HbE Doi-Saket). Phenotypic expression was clinically silent in heterozygotes and might present slight microcytosis. CONCLUSIONS: Hb Doi-Saket emphasizes a great diversity present in α-globin gene. The mutation in this family from Thailand was linked to -α3.7 and caused mild microcytosis in the carriers. The combination of this variant with deletions in α genes might cause a severe clinical phenotype. Different methods of separation can provide useful information in diagnosis, and a complete molecular approach is needed for confirmation before considering patient management.


The Hb Doi-Saket is a novel α-globin variant mutation occurring in the α2-globin gene in cis to the -α3.7 kb chromosome.The carrier of Hb Doi-Saket may present slight microcytosis and have severe clinical entities when it interacts with deletions in α-globin genes.Hb analysis with the HPLC system could completely separate Hb Doi-Saket and its derivative from other Hbs.


Asunto(s)
Hemoglobina E , Hemoglobinas Anormales , Talasemia alfa , Humanos , Hemoglobina E/genética , Tailandia , Pueblos del Sudeste Asiático , Talasemia alfa/diagnóstico , Talasemia alfa/genética , Hemoglobinas Anormales/genética , Mutación , ADN , Globinas alfa/genética
12.
Stem Cell Res ; 73: 103228, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37890329

RESUMEN

Hemoglobin E (HbE), a common variant in Southeast Asian populations, results from a G to A substitution at codon 26 of the HBB gene, causing abnormal Hb and mild ß-thalassemia-like symptoms. Here, we derived an induced pluripotent stem cell (iPSC) line, named MUi033-A, from a male homozygous for HbE. The iPSC line demonstrates a normal karyotype and embryonic stem cell-like properties including pluripotency gene expression, and tri-lineage differentiation potential. This iPSC resource holds the potential for investigating gene therapy targeting HbE mutation.


Asunto(s)
Hemoglobina E , Células Madre Pluripotentes Inducidas , Talasemia beta , Humanos , Masculino , Hemoglobina E/genética , Hemoglobina E/metabolismo , Células Madre Pluripotentes Inducidas/metabolismo , Mutación , Talasemia beta/genética , Talasemia beta/metabolismo , Talasemia beta/terapia , Homocigoto
13.
Ann Med ; 55(2): 2267054, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37816374

RESUMEN

BACKGROUND: Low HbF expression in HbE-ß+-thalassemia may lead to misdiagnosis of HbE heterozygosity. We aimed to characterize the ß- and α-globin genes and the modifying factors related to HbF expression in patients with an Hb phenotype similar to that of HbE heterozygotes. Furthermore, screening tools for differentiating HbE-ß+-thalassemia from HbE heterozygotes have been investigated. PARTICIPANTS AND METHODS: A total of 2133 participants with HbE and HbA with varying HbF levels were recruited. Polymerase chain reaction-based DNA analysis and sequencing were performed to characterize ß- and α-globin genes. DNA polymorphism at position -158 nt 5' to Gγ-globin was performed by XmnI restriction digestion. Receiver operating characteristic (ROC) curves were constructed using the area under the curve (AUC). Cutoff values of HbA2, HbE, and HbF levels for the differentiation of HbE-ß+-thalassemia from HbE heterozygotes were determined. RESULTS: Five ß+-thalassemia mutations trans to ßE-gene (ß-87(C>A), ß-31(A>G), ß-28(A>G), ß19(A>G), and ß126(T>G)) were identified in 79 patients. Among these, 54 presented with low HbF levels, and 25 presented with high HbF levels. ROC curve analysis revealed an excellent AUC of 1.000 (95% confidence interval:1.000-1.000) for HbE levels, and a cut-off point of ≥35.0% had 100.0% sensitivity, specificity, and Youden's index for differentiating HbE-ß+-thalassemia from HbE heterozygotes. The proportion of α-thalassemia mutations was 46.3 and 8.0% among HbE-ß+-thalassemia patients with low and high HbF levels, respectively. Two rare α-thalassemia mutations (Cap +14(C>G) and initiation codon (ATG>-TG)) of α2-globin genes were identified. The genotype and allele of the polymorphism at -158 nt 5' to Gγ-globin was found to be negatively associated with HbF expression. CONCLUSIONS: HbE-ß+-thalassemia cannot be disregarded until appropriate DNA analysis is performed, and the detection of α-thalassemia mutations should always be performed under these conditions. An HbE level ≥35.0% may indicate screening of samples for DNA analysis for HbE-ß+-thalassemia diagnosis.


HbE-ß+-thalassemia displays a wide range of HbF expression, which may lead to the misdiagnosis of HbE heterozygosity in patients whose Hb analysis shows HbE and HbA. α-Thalassemia may be a major factor associated with decreased secondary activation of HbF expression in the disease.HbE may be a potential indicator for effectively differentiating HbE-ß+-thalassemia from HbE heterozygotes.The high proportion and heterogeneity of α-thalassemia mutations found in patients with HbE-ß+-thalassemia evoke a complex thalassemia syndrome, requiring complete DNA analysis.


Asunto(s)
Hemoglobina E , Talasemia alfa , Talasemia beta , Humanos , Heterocigoto , gamma-Globinas/genética , Hemoglobina E/genética , Hemoglobina E/análisis , Hemoglobina E/metabolismo , Hemoglobina Fetal/genética , Hemoglobina Fetal/análisis , Hemoglobina Fetal/metabolismo , Talasemia beta/diagnóstico , Talasemia beta/genética , Fenotipo , ADN , Globinas alfa/genética
14.
Biochem Med (Zagreb) ; 33(3): 030801, 2023 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-37841770

RESUMEN

The gold standard for long-term monitoring of diabetic patients is glycated haemoglobin (HbA1c), which is routinely tested for glycaemic control. Furthermore, the National glycohemoglobin standardization program (NGSP) has designated high-performance liquid chromatography (HPLC) as the reference method for HbA1c measurement. A woman from the Sumba tribe, Indonesia, aged 52, visited the Internal Medicine Clinic for a routine check-up. She had been taking diabetic and hypertension medicines on a regular basis for over 10 years. The HPLC procedure yielded "no result" for the patient's HbA1c assessment and there was no peak on the HPLC graphic. However, there was a discrepancy between the data history of HbA1c measured by turbidimetric method (average of 51 mmol/mol, reference range < 48 mmol/mol), fasting blood glucose (average of 7.7 mmol/L, reference range < 7.0 mmol/L) and 2-hour plasma glucose (average of 13 mmol/L, reference range < 11.1 mmol/L). Glycated albumin was 3.1 mmol/L (reference range 1.8-2.4 mmol/L). Haemoglobin electrophoresis identified homozygote haemoglobinopathy E (HbE). Patients with haemoglobin variants are proposed to utilize glycated albumin.


Asunto(s)
Diabetes Mellitus Tipo 2 , Diabetes Mellitus , Hemoglobina E , Femenino , Humanos , Hemoglobina Glucada , Cromatografía Líquida de Alta Presión , Hemoglobina E/análisis , Fenotipo , Albúminas , Glucemia
15.
Blood Cells Mol Dis ; 103: 102781, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37478523

RESUMEN

Ineffective erythropoiesis is the main cause of anemia in ß-thalassemia. The crucial hallmark of ineffective erythropoiesis is the high proliferation of erythroblast. microRNA (miR/miRNA) involves several biological processes, including cell proliferation and erythropoiesis. miR-101 was widely studied and associated with proliferation in several types of cancer. However, the miR-101-3p has not been studied in ß-thalassemia/HbE. Therefore, this study aims to investigate the expression of miR-101-3p during erythropoiesis in ß-thalassemia/HbE. The results showed that miR-101-3p was upregulated in the erythroblast of ß-thalassemia/HbE patients on day 7, indicating that miR-101-3p may be involved with high proliferation in ß-thalassemia/HbE. Therefore, the mRNA targets of miR-101-3p including Rac1, SUB1, TET2, and TRIM44 were investigated to determine the mechanisms involved with high proliferation of ß-thalassemia/HbE erythroblasts. Rac1 expression was significantly reduced at day 11 in severe ß-thalassemia/HbE compared to normal controls and mild ß-thalassemia/HbE. SUB1 gene expression was significantly lower in severe ß-thalassemia/HbE compared to normal controls at day 9 of culture. For TET2 and TRIM44 expression, a significant difference was not observed among normal and ß-thalassemia/HbE. However, the high expression of miR-101-3p at day 7 and these target genes was not correlated, suggesting that this miRNA may regulate ineffective erythropoiesis in ß-thalassemia/HbE via other target genes.


Asunto(s)
Hemoglobina E , MicroARNs , Talasemia beta , Humanos , Talasemia beta/complicaciones , Talasemia beta/genética , Talasemia beta/metabolismo , MicroARNs/genética , Eritropoyesis/genética , Regulación hacia Arriba , Hemoglobina E/genética , Proteínas de Motivos Tripartitos/genética , Proteínas de Motivos Tripartitos/metabolismo , Péptidos y Proteínas de Señalización Intracelular/genética , Péptidos y Proteínas de Señalización Intracelular/metabolismo
16.
Blood Cells Mol Dis ; 103: 102765, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37353362

RESUMEN

The study aimed to identify essential phenotype-modulating factors among the pre-existence of several important ones and clarify their measurable impact on the clinical severity of hemoglobin (Hb) E/ß-thalassemia in a community-recruited population analysis. This prospective study was designed to compare modifiers between community- (less or no symptoms) and hospital-recruited individuals with Hb E/ß-thalassemia. The formerly included couples previously assessed for prenatal thalassemia at-risk status at 42 community and 7 referral hospitals in Thailand through on-site investigations between June 2020 and December 2021. The control included Hb E/ß-thalassemia patients undergoing transfusions. The Mahidol score classified disease severity. Beta-globin, α0-thalassemia (-SEA, -THAI), α+-thalassemia (-α3.7, -α4.2), Hb Constant Spring (αCS) alleles, rs766432 in BCL11A, rs9399137 in HBS1L-MYB, and rs7482144-XmnI were evaluated. Modifiers were compared between 102 community- and 104 hospital-recruited cases. Alleles of ß+, -SEA, -α3.7, αCS, and a minor allele of rs9399137 were prevalent in the community and mild severity groups (p < 0.05). Multiple linear regression analysis associated modulating alleles with -4.299 (-SEA), -3.654 (ß+), -3.065 (rs9399137, C/C), -2.888 (αCS), -2.623 (-α3.7), -2.361 (rs7482144, A/A), -1.258 (rs9399137, C/T), and -1.174 (rs7482144, A/G) severity score reductions (p < 0.05). Certain modifiers must be considered in routine prenatal genetic counseling for Hb E/ß-thalassemia.


Asunto(s)
Hemoglobina E , Talasemia alfa , Talasemia beta , Humanos , Talasemia beta/epidemiología , Talasemia beta/genética , Talasemia beta/terapia , Hemoglobina E/genética , Hemoglobina E/análisis , Polimorfismo de Nucleótido Simple , Estudios Prospectivos , Asesoramiento Genético , Talasemia alfa/epidemiología , Talasemia alfa/genética , Talasemia alfa/terapia , Genotipo
17.
Nat Commun ; 14(1): 2238, 2023 04 19.
Artículo en Inglés | MEDLINE | ID: mdl-37076455

RESUMEN

Haemoglobin E (HbE) ß-thalassaemia causes approximately 50% of all severe thalassaemia worldwide; equating to around 30,000 births per year. HbE ß-thalassaemia is due to a point mutation in codon 26 of the human HBB gene on one allele (GAG; glutamatic acid → AAG; lysine, E26K), and any mutation causing severe ß-thalassaemia on the other. When inherited together in compound heterozygosity these mutations can cause a severe thalassaemic phenotype. However, if only one allele is mutated individuals are carriers for the respective mutation and have an asymptomatic phenotype (ß-thalassaemia trait). Here we describe a base editing strategy which corrects the HbE mutation either to wildtype (WT) or a normal variant haemoglobin (E26G) known as Hb Aubenas and thereby recreates the asymptomatic trait phenotype. We have achieved editing efficiencies in excess of 90% in primary human CD34 + cells. We demonstrate editing of long-term repopulating haematopoietic stem cells (LT-HSCs) using serial xenotransplantation in NSG mice. We have profiled the off-target effects using a combination of circularization for in vitro reporting of cleavage effects by sequencing (CIRCLE-seq) and deep targeted capture and have developed machine-learning based methods to predict functional effects of candidate off-target mutations.


Asunto(s)
Hemoglobina E , Talasemia , Talasemia beta , Humanos , Animales , Ratones , Talasemia beta/genética , Hemoglobina E/genética , Talasemia/genética , Mutación , Mutación Puntual
18.
Hematol Oncol Clin North Am ; 37(2): 313-325, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36907605

RESUMEN

This article reviews the classification of beta-thalassemia syndromes, correlating clinical severity and genotype in the earlier classification, and broadening it recently based on clinical severity and transfusion status. The classification is dynamic, and individuals may progress from transfusion-independent to transfusion-dependent. Early and accurate diagnosis prevents delays in instituting treatment and comprehensive care, and precludes inappropriate and potentially harmful interventions. Screening can inform risk in an individual and subsequent generations when partners may be carriers as well. This article discusses the rationale for screening of the at-risk population. In the developed world, a more precise genetic diagnosis must be considered.


Asunto(s)
Hemoglobina E , Talasemia , Talasemia beta , Humanos , Talasemia beta/genética , Hemoglobina E/genética , Talasemia/terapia , Genotipo
19.
Hematology ; 28(1): 2187155, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36939018

RESUMEN

OBJECTIVES: Clinical manifestations of patients with Hemoglobin E/beta-thalassemia vary from mild to severe phenotypes despite exhibiting the same genotype. Studies have partially identified genetic modifiers. We aimed to study the association between rare variants in protein-coding regions and clinical severity in Thai patients. METHODS: From April to November 2018, a case-control study was conducted based on clinical information and DNA samples collected from Thai patients with hemoglobin E/beta-thalassemia over the age of four years. Cases were patients with severe symptoms, while patients with mild symptoms acted as controls. Whole exome sequencing and rare variant association study were used to analyze the data. RESULTS: All 338 unrelated patients were classified into 165 severe and 173 mild cases. Genotypes comprised 81.4% of hemoglobin E/beta-thalassemia, 2.7% of homozygous or compound heterozygous beta-thalassemia, and 0.3% of (뫧)0 thalassemia Hb E while 15.7% of samples were not classified as beta-thalassemia. A novel cis heterozygotes of IVS I-7 (A > T) and codon 26 (G > A) was identified. Six genes (COL4A3, DLK1, FAM186A, PZP, THPO, and TRIM51) showed the strongest associations with severity (observed p-values of <0.05; significance lost after correction for multiplicity). Among known modifiers, KLF1 variants were found in four mild patients and one severe patient. CONCLUSION: No rare variants were identified as contributors to the clinical heterogeneity of hemoglobin E/beta-thalassemia. KLF1 mutations are potential genetic modifiers. Studies to identify genetic factors are still important and helpful for predicting severity and developing targeted therapy.


Asunto(s)
Hemoglobina E , Factores de Transcripción de Tipo Kruppel , Talasemia beta , Humanos , Talasemia beta/genética , Talasemia beta/diagnóstico , Estudios de Casos y Controles , Secuenciación del Exoma , Hemoglobina E/genética , Mutación , Pueblos del Sudeste Asiático , Factores de Transcripción de Tipo Kruppel/genética
20.
BMJ Case Rep ; 16(2)2023 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-36750295

RESUMEN

Haemoglobin E (HbE) affects at least 1 million people around the world. The carrier frequency of HbE/beta-thalassaemia (HbE/ß-thalassaemia) is highest in Southeast Asia. In India, the highest frequency is observed in the northeast region. Distinguishing between homozygous HbE disease and HbE/ß-thalassaemia is a challenge to the haematopathologist as well as to the treating obstetrician because both are clinically and haematologically similar, posing a difficulty in managing anaemia and assessing the fetal risk for the same disease. This article reports a case of compound heterozygote HbE/ß-thalassaemia in pregnancy and its successful outcome.


Asunto(s)
Hemoglobina E , Talasemia , Talasemia beta , Femenino , Humanos , Embarazo , Heterocigoto , Hemoglobina E/análisis , Hemoglobina E/genética , Talasemia beta/terapia , India
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