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1.
Acta méd. costarric ; 62(1): 38-42, ene.-mar. 2020. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-1088534

RESUMO

Resumen La enfermedad por hemoglobina H es un cuadro clínico que se presenta en las alfa talasemias, las cuales son enfermedades que cursan con anemia microcítica hipocrómica, debidas principalmente a deleciones en el gen de alfaglobina, lo que disminuye la producción de la cadena de alfa globina y promueve la formación de variantes de hemoglobina. Cuando se detectan variantes de hemoglobina en las alfa talasemias, por lo general, se debe a genotipos homocigotas o dobles heterocigotas para mutaciones y deleciones del gen de alfa globina coheredadas. En este artículo se describe el primer caso en Costa Rica, de dos hermanos con enfermedad por hemoglobina H, que fenotípicamente presentaron las variantes de hemoglobina H y hemoglobina Constant Spring en el análisis electroforético de la hemoglobina, y cuyo análisis molecular del gen de alfa globina detectó tanto la deleción sudeste asiático como la mutación para hemoglobina Constant Spring, siendo diagnosticados como dobles heterocigotos por alfa talasemia (genotipo --SEA/ααCS).


Abstract Hemoglobin H disease occurs in patients with alpha thalassemia, diseases associated with hypochromic microcytic anemia, mainly due to deletions in the alpha globin gene, which decreases the production of the alpha globin chain and promotes the formation of hemoglobin variants. When hemoglobin variants are detected in alpha thalassemias it is usually due to homozygoys or doublé heterozygous genotypes, for mutations and deletions of the alpha globin gene. This article describes the first case in Costa Rica of two siblings with hemoglobin H disease, who phenotypically presented the hemoglobin H and Constant Spring hemoglobin variants in the electrophoretic analysis of the hemoglobin, and whose molecular DNA analysis of the alpha globin gene detected both, the Southeast Asian deletion and the mutation for Constant Spring Hemoglobin, being diagnosed as compound heterozygous for alpha thalassemia (genotipe --SEA/ααCS).


Assuntos
Humanos , Feminino , Lactente , Hemoglobina H , Talassemia alfa , Costa Rica , Hemoglobinopatias/genética , Triagem de Portadores Genéticos , Anemia Hipocrômica
2.
Indian J Med Res ; 150(2): 161-166, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31670271

RESUMO

Background & objectives: Swiss-type hereditary persistence of foetal haemoglobin (HPFH) has been shown to be responsible for the wide range of F cell levels in healthy Thai adults. However, a survey for F cells in healthy Thai adults has not been performed. This study was conducted to determine the F cell distribution in adult Thai blood donors and to assess the possible involvement of ß-thalassaemia and haemoglobin E (HbE) carriers in increased HbF levels. Methods: Thai blood donors (n=375, 205 males and 170 females) were included in the study. Blood samples were collected for measuring haemoglobin (Hb) concentration and haematocrit (Hct) and F cell levels. Hb and Hct levels were determined by automated blood counter, while F cells were quantified by flow cytometric analysis of F cells stained by fluorescein isothiocyanate-conjugated anti γ-globin monoclonal antibody. Finally, F cell levels were compared between blood samples having mean corpuscular volume (MCV ) <80 fl and ≥80 fl as well as between ß-haemoglobinopathies (HbE and ß-thalassaemia carriers) and normal adults. Results: F cell levels varied markedly spanning 0.80-39.2 per cent with a positively skewed distribution. Thirty two per cent of these individuals had F cell levels more than the 4.5 per cent cut-off point. F cell levels in females were significantly higher than those in males (P<0.05). F cell levels in individuals having MCV <80 fl were significantly higher than those having MCV ≥80 fl (P<0.05). ß-haemoglobinopathy (HbE and ß-thalassaemia carriers) had significantly higher F cell levels than normal individuals (P<0.05). Interpretation & conclusions: The present results showed that besides Swiss-type HPFH, the ß-haemoglobinopathy was expected to be involved in increased F cell levels in adult Thais. Thus, influence of ß-haemoglobinopathy must be considered in interpreting F cell levels in area endemic of this globin disorder.


Assuntos
Hemoglobina Fetal/genética , Hemoglobina E/genética , Hemoglobinopatias/genética , Talassemia beta/genética , Adulto , Anemia Falciforme/sangue , Anemia Falciforme/epidemiologia , Anemia Falciforme/genética , Anemia Falciforme/patologia , Doadores de Sangue , Pré-Escolar , Índices de Eritrócitos/genética , Feminino , Hemoglobinopatias/sangue , Hemoglobinopatias/epidemiologia , Hemoglobinopatias/patologia , Heterozigoto , Humanos , Lactente , Recém-Nascido , Masculino , Fenótipo , Tailândia , Talassemia beta/sangue , Talassemia beta/epidemiologia , Talassemia beta/patologia
3.
Hemoglobin ; 43(4-5): 223-228, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31603010

RESUMO

ß-Thalassemia (ß-thal) is a genetic disorder representing a major health problem in Algeria. Our first objective was to determine the allelic frequencies and molecular spectrum of ß-thal mutations in patients with major hemoglobinopathies [ß-thal major (ß-TM) and sickle cell disease] in three provinces of northeast Algeria. Our second objective was to assess if the clinical management of ß-TM patients depended on their region of origin. Our last objective was to assess a population originating from Maghreb, the reliability of the thalassemia severity score (TSS) for patients with homozygous ß-thal. Sanger HBB gene sequencing was performed on 59 patients with sickle cell disease and 60 with ß-TM. For the latter patients, the genetic modifiers of the TSS were genotyped: α-thalassemia (α-thal) deletions and four Hb F-inducing polymorphisms (XmnI, rs1427407 and rs10189857 for BCL11A and rs9399137 for HMIP). Eleven different ß-thal mutations were found but two of them (HBB: c.118C>T and HBB: c.93-21G>A) accounted for about 70.0% of the ß-thal alleles. A relatively high proportion of Hb S (HBB: c.20A>T)/ß-thal genotypes (27.0%) was found in our sickle cell disease cohort where a new frameshift ß0-thal mutation (HBB: c.374dup; p.Pro126Thrfs*15) was identified. No difference was found in the three provinces. Of the 60 ß-TM patients, those with a high or very high TSS were significantly younger at the age of first transfusion, thus assessing the reliability of this scoring system in a Maghrebin cohort. Trends for a lower age of splenectomy and high ferritin levels were also detected for the higher TSS categories.


Assuntos
Índice de Gravidade de Doença , Talassemia beta/genética , Adulto , Argélia/epidemiologia , Anemia Falciforme/genética , Transfusão de Sangue , Feminino , Ferritinas/sangue , Mutação da Fase de Leitura , Genótipo , Hemoglobina Falciforme/genética , Hemoglobinopatias/genética , Humanos , Masculino , Esplenectomia , Talassemia beta/epidemiologia
4.
Hemoglobin ; 43(4-5): 254-257, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31599656

RESUMO

To provide the molecular information on hemoglobinopathies in the Myanmar population, the study was carried out on Myanmar workers in Khon Kaen Province in northeast Thailand. A total of 300 anonymous Myanmar factory workers were randomly recruited during their annual medical checkup. Hemoglobinopathies were identified using hemoglobin (Hb) and DNA analyses. These identified heterozygous α0-thalassemia (α0-thal) [- -SEA (Southeast Asian) deletion] (n = 5, 1.7%), heterozygous α+-thal (n = 103, 34.3%), homozygous α+-thal (n = 12, 4.0%), heterozygous ß-thalassemia (ß-thal) (n = 3, 1.0%), heterozygous ß-thal with homozygous α+-thal (n = 2, 0.7%), double heterozygous ß-thal/α0-thal (n = 1, 0.3%)], heterozygous Hb E (HBB: c.79G>A) with α0-thal/α+-thal (n = 1, 0.3%), heterozygous Hb E (n = 27, 9.0%), heterozygous Hb E with α+-thal (n = 24, 8.0%), homozygous Hb E with α0-thal/α+-thal (n = 1, 0.3%), homozygous Hb E (n = 3, 1.0%) and homozygous Hb E with heterozygous α+-thal (n = 3, 1.0%). No thalassemia defect was found in the remaining 115 subjects (38.4%). Haplotypes associated with Hb E and Hb Dhonburi (or Hb Neapolis) [ß126(H4)Val→Gly, codon 126 (T>G), HBB: c.380T>G] are reported. While the proportions of α0-thal, ß-thal and Hb E are comparable to those described in neighboring countries, a markedly high prevalence of α+-thal (48.6% in total) is unexpected. The molecular information obtained should provide necessary information for diagnostic improvement and planning of a prevention and control program of severe thalassemia in the Myanmar population.


Assuntos
Hemoglobinopatias/genética , Talassemia alfa/etnologia , Hemoglobina E , Hemoglobinopatias/etnologia , Hemoglobinas/análise , Hemoglobinas Anormais , Humanos , Mianmar/etnologia , Prevalência , Análise de Sequência de DNA , Tailândia/epidemiologia
5.
Hemoglobin ; 43(4-5): 249-253, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31581858

RESUMO

This study assessed thalassemia and hemoglobinopathies in a group of the Tay ethnic minority. Participants included 289 women of reproductive-age who enrolled in a pilot screening program for thalassemia conducted at six communities of Thai Nguyen Province, northern Vietnam. Standard procedures including complete blood count (CBC), hemoglobin (Hb) and DNA analyses were performed for all samples. The prevalence of thalassemia in 289 Tay women was 15.6% (gene frequency 0.078) for α0-thalassemia (α0-thal), 10.0% (gene frequency 0.050) for α+-thal, 7.3% (gene frequency 0.036) for ß-thalassemia (ß-thal), 2.4% (gene frequency 0.012) for Hb Constant Spring [Hb CS; α142, Term→Gln, TAA>CAA (α2), HBA2: c.427T>C] and 1.7% (gene frequency 0.009) for Hb E [ß26(B8)Glu→Lys, GAG>AAG; HBB: c.79G>A]. Further analysis of ß-globin gene abnormalities identified four mutations including codons 41/42 (-TCTT) (HBB: c.126_129delCTTT), codon 17 (A>T) (HBB: c.52A>T), codons 71/72 (+A) (HBB: c.216_217insA), and -28 (A>G) (HBB: c.78A>G). The results hint at the remarkably high frequencies of severe forms of thalassemia that indicate a serious public health problem requiring further exploration, and most probably, also intervention within the country.


Assuntos
Hemoglobinopatias/etnologia , Grupos Minoritários , Talassemia/etnologia , Grupos Étnicos , Feminino , Frequência do Gene , Hemoglobinopatias/genética , Hemoglobinas Anormais , Humanos , Programas de Rastreamento , Mutação , Prevalência , Talassemia/genética , Vietnã/epidemiologia , Vietnã/etnologia , Talassemia alfa/etnologia , Talassemia alfa/genética , Globinas beta/genética , Talassemia beta/etnologia , Talassemia beta/genética
7.
Pediatr. aten. prim ; 21(83): e125-e127, jul.-sept. 2019.
Artigo em Espanhol | IBECS | ID: ibc-188639

RESUMO

Las hemoglobinopatías son resultado de mutaciones en los genes responsables de la estructura molecular de la hemoglobina. Tienen una expresividad clínica muy variable: desde mínimamente sintomáticas a patología grave. Presentamos el caso de un niño de tres años ingresado por una neumonía atípica con hipoxemia que, tras 11 días de ingreso, mantiene saturaciones periféricas de oxígeno (SpO) de 92-94% sin otra sintomatología, exploración física y estudio cardiopulmonar normal. En el seguimiento ambulatorio persiste la desaturación periférica con gasometría y cooximetría arterial normal. El padre del paciente presenta los mismos hallazgos tanto en la pulsioximetría como en la gasometría arterial. Ante la sospecha de una hemoglobinopatía estructural se realiza estudio genético y electroforético detectándose la presencia de hemoglobina Arta


Structural hemoglobinopathies are the result of gene mutations that cause alterations in the molecular structure of hemoglobin. They have a very variable clinical expression: from minimally symptomatic to severe pathology. We present the case of a 3-year-old boy admitted for atypical pneumonia with hypoxemia who, after 11 days of admission, maintained peripheral oxygen saturations (SpO) of 92-94% without other symptoms, physical examination and normal cardiopulmonary study. In outpatient follow-up, peripheral desaturation persists with gasometry and normal arterial co-oxymetry. Patient's father with the same findings in pulse oximetry as in arterial blood gases. When a structural hemoglobinopathy was suspected, a genetic and electrophoretic study was performed, detecting the presence of hemoglobin Arta


Assuntos
Humanos , Masculino , Pré-Escolar , Hipóxia/etiologia , Hemoglobinopatias/genética , Oximetria/métodos , Hemoglobinas/análise , Pneumonia/diagnóstico , Doenças Genéticas Inatas/genética , Testes Genéticos/métodos
8.
Yi Chuan ; 41(8): 746-753, 2019 Aug 20.
Artigo em Chinês | MEDLINE | ID: mdl-31447425

RESUMO

Personal genomic information benefits from accumulated big data and its application is no longer limited to scientific research. Presently, it is undergoing the transformation to daily medical practice. Systematic arrangement, archiving and rational utilization of disease-related genomic information is an important foundation of future precision medicine. Hemoglobinopathy is prevalent in southern China, but its molecular pathological basis has racial specificity. To facilitate clinical diagnosis and genetic screening of hemoglobinopathy in southern China, we established the LOVD gene data management system for the variation and phenotype spectrum of hemoglobinopathy. Then we designed an integrated and efficient on-line auxiliary accurate diagnosis and risk assessment system in order to assist clinicians to make comprehensive diagnosis and genetic counseling in a short time based on cloud standardized annotated library of specific hemoglobinopathy variants and diagnostic repository. The methodology and experience of improving the clinical decision-making efficiency of diseases with big data and artificial intelligence technology can be used as an example in the clinical and preventive application of other diseases.


Assuntos
Bases de Dados Genéticas , Sistemas de Apoio a Decisões Clínicas , Hemoglobinopatias/genética , Mutação , China , Aconselhamento Genético , Testes Genéticos , Humanos
9.
Hemoglobin ; 43(3): 214-217, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31450984

RESUMO

We report the molecular and hematological identifications of a Hb A2 variant [coinheritance of Hb A2-Melbourne (HBD: c.130G>A) and Hb E (HBB: c.79G>A)] found for the first time in the Lao People's Democratic Republic (PDR). The subject was a 29-year-old pregnant Laotian woman who was a foreign worker in Thailand and was diagnosed with thalassemia and hemoglobinopathies. Capillary electrophoresis (CE) demonstrated 1.6% of Hb A2, with a minor unknown peak at the initial Z1 zone (1.7%). Identification of abnormal hemoglobin (Hb) using direct DNA sequencing showed a genetic defect causing a δ-globin gene missense mutation at codon 43 (GAG>AAG) causing a glutamic acid to lysine substitution corresponding to Hb A2-Melbourne. The origin of Hb A2-Melbourne in Lao PDR may be similar to a case found in Thailand with the [+ - - - - + +] haplotype. We developed a method that could clearly detect Hb A2-Melbourne and Hb A2-Lampang (HBD: c.142G>A) mutations in a single tube using high resolution melt (HRM) analysis. The HRM analysis is a more effective method for rapid detection than conventional polymerase chain reaction (PCR), as there is no need for a post-PCR step, and no exposure to ethidium bromide. This new method would be a useful addition for the first investigation of a suspected Hb A2 variant in the routine molecular setting.


Assuntos
Alelos , Genótipo , Hemoglobina E/genética , Hemoglobinas Anormais/genética , Padrões de Herança , Mutação , Biomarcadores , Análise Mutacional de DNA , Índices de Eritrócitos , Feminino , Hemoglobinopatias/diagnóstico , Hemoglobinopatias/genética , Humanos , Laos , Reação em Cadeia da Polimerase , Gravidez
10.
Hemoglobin ; 43(3): 207-209, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31387435

RESUMO

We describe here a previously unreported hemoglobin (Hb) variant, Hb Gibbon [ß124(H2)Pro→Thr (HBB: c.373C>A, p.P125T)] detected by newborn Hb screening in a term male with no family history for hemoglobinopathy or other screening abnormalities. This missense mutation produces a ß-globin chain variant that was detected by high performance liquid chromatography (HPLC) methods, but is silent by capillary electrophoresis (CE). DNA sequencing studies revealed that his father was also a heterozygote for this mutation. Neither has abnormalities on complete blood count (CBC) or any symptomatology.


Assuntos
Alelos , Substituição de Aminoácidos , Doenças Assintomáticas , Hemoglobinopatias/diagnóstico , Hemoglobinopatias/genética , Globinas beta/genética , Cromatografia Líquida de Alta Pressão , Análise Mutacional de DNA , Genótipo , Hemoglobinas Anormais/genética , Humanos , Recém-Nascido , Triagem Neonatal , Globinas beta/análise , Globinas beta/metabolismo
11.
Pharmacogenomics ; 20(11): 791-801, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31393228

RESUMO

Aim: ß-Type hemoglobinopathies are characterized by vast phenotypic diversity as far as disease severity is concerned, while differences have also been observed in hydroxyurea (HU) treatment efficacy. These differences are partly attributed to the residual expression of fetal hemoglobin (HbF) in adulthood. The Krüppel-like family of transcription factors (KLFs) are a set of zinc finger DNA-binding proteins which play a major role in HbF regulation. Here, we explored the possible association of variants in KLF gene family members with response to HU treatment efficacy and disease severity in ß-hemoglobinopathies patients. Materials & methods: Six tag single nucleotide polymorphisms, located in four KLF genes, namely KLF3, KLF4, KLF9 and KLF10, were analyzed in 110 ß-thalassemia major patients (TDT), 18 nontransfusion dependent ß-thalassemia patients (NTDT), 82 sickle cell disease/ß-thalassemia compound heterozygous patients and 85 healthy individuals as controls. Results: Our findings show that a KLF4 genomic variant (rs2236599) is associated with HU treatment efficacy in sickle cell disease/ß-thalassemia compound heterozygous patients and two KLF10 genomic variants (rs980112, rs3191333) are associated with persistent HbF levels in NTDT patients. Conclusion: Our findings provide evidence that genomic variants located in KLF10 gene may be considered as potential prognostic biomarkers of ß-thalassemia clinical severity and an additional variant in KLF4 gene as a pharmacogenomic biomarker, predicting response to HU treatment.


Assuntos
Anemia Falciforme/tratamento farmacológico , Fatores de Transcrição de Resposta de Crescimento Precoce/genética , Hemoglobinopatias/tratamento farmacológico , Fatores de Transcrição Kruppel-Like/genética , Talassemia beta/tratamento farmacológico , Anemia Falciforme/sangue , Anemia Falciforme/epidemiologia , Anemia Falciforme/genética , Biomarcadores Farmacológicos/metabolismo , Feminino , Hemoglobina Fetal/genética , Estudos de Associação Genética , Hemoglobinopatias/sangue , Hemoglobinopatias/epidemiologia , Hemoglobinopatias/genética , Humanos , Hidroxiureia/administração & dosagem , Hidroxiureia/efeitos adversos , Masculino , Polimorfismo de Nucleotídeo Único/genética , Índice de Gravidade de Doença , Resultado do Tratamento , Talassemia beta/sangue , Talassemia beta/epidemiologia , Talassemia beta/genética
12.
Blood ; 134(15): 1203-1213, 2019 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-31467062

RESUMO

ß-Thalassemia and sickle cell disease (SCD) are the most prevalent monogenic diseases. These disorders are caused by quantitative or qualitative defects in the production of adult hemoglobin. Gene therapy is a potential treatment option for patients lacking an allogenic compatible hematopoietic stem cell (HSC) donor. New-generation lentiviral vectors (LVs) carrying a ß-globin-like gene have revolutionized this field by allowing effective HSC transduction, with no evidence of genotoxicity to date. Several clinical trials with different types of vector are underway worldwide; the initial results are encouraging with regard to the sustained production of therapeutic hemoglobin, improved biological parameters, a lower transfusion requirement, and better quality of life. Long-term follow-up studies will confirm the safety of LV-based gene therapy. The optimization of patient conditioning, HSC harvesting, and HSC transduction has further improved the therapeutic potential of this approach. Novel LV-based strategies for reactivating endogenous fetal hemoglobin (HbF) are also promising, because elevated HbF levels can reduce the severity of both ß-thalassemia and SCD. Lastly, genome-editing approaches designed to correct the disease-causing mutation or reactivate HbF are currently under investigation. Here, we discuss the clinical outcomes of current LV-based gene addition trials and the promising advantages of novel alternative therapeutic strategies.


Assuntos
Hemoglobina Fetal/genética , Edição de Genes/métodos , Terapia Genética/métodos , Hemoglobinopatias/terapia , Globinas beta/genética , Anemia Falciforme/genética , Anemia Falciforme/terapia , Animais , Ensaios Clínicos como Assunto , Terapia Genética/efeitos adversos , Vetores Genéticos/genética , Vetores Genéticos/uso terapêutico , Hemoglobinopatias/genética , Humanos , Lentivirus/genética , Talassemia beta/genética , Talassemia beta/terapia
13.
Hemoglobin ; 43(3): 204-206, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31397596

RESUMO

We describe Hb Alcorn County, a heterozygous hemoglobin (Hb) variant, in a 6-month-old Hispanic male and his mother. DNA sequencing demonstrated a mutation on the HBB gene [ß40(C6)Arg→Thr; HBB: c.122G>C (p.Arg41Thr)], predictive of a substitution of arginine to threonine at position 40 of the ß-globin protein. This amino acid substitution involves the α1ß2 contact and occurs at the same position as Hb Austin [ß40(C6)Arg→Ser; HBB: c.[123G>C or 123G>T] (p.Arg41Ser)] and Hb Athens-GA [ß40(C6)Arg→Lys; HBB: c.122G>A (p.Arg41Lys)], both of which show increased oxygen affinity.


Assuntos
Alelos , Substituição de Aminoácidos , Mutação , Oxigênio/metabolismo , Globinas beta/genética , Globinas beta/metabolismo , Cromatografia Líquida de Alta Pressão , Análise Mutacional de DNA , Predisposição Genética para Doença , Genótipo , Hemoglobinopatias/diagnóstico , Hemoglobinopatias/genética , Hemoglobinopatias/metabolismo , Humanos , Lactente , Masculino , Fenótipo , Ligação Proteica , Globinas beta/análise
14.
Hum Mutat ; 40(12): 2221-2229, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31286593

RESUMO

Hemoglobinopathies are the most common monogenic disorders worldwide. Substantial effort has been made to establish databases to record complete mutation spectra causing or modifying this group of diseases. We present a variant database which couples an online auxiliary diagnosis and at-risk assessment system for hemoglobinopathies (DASH). The database was integrated into the Leiden Open Variation Database (LOVD), in which we included all reported variants focusing on a Chinese population by literature peer review-curation and existing databases, such as HbVar and IthaGenes. In addition, comprehensive mutation data generated by high-throughput sequencing of 2,087 hemoglobinopathy patients and 20,222 general individuals from southern China were also incorporated into the database. These sequencing data enabled us to observe disease-causing and modifier variants responsible for hemoglobinopathies in bulk. Currently, 371 unique variants have been recorded; 265 of 371 were described as disease-causing variants, whereas 106 were defined as modifier variants, including 34 functional variants identified by a quantitative trait association study of this high-throughput sequencing data. Due to the availability of a comprehensive phenotype-genotype data set, DASH has been established to automatically provide accurate suggestions on diagnosis and genetic counseling of hemoglobinopathies. LOVD-DASH will inspire us to deal with clinical genotyping and molecular screening for other Mendelian disorders.


Assuntos
Bases de Dados Genéticas , Hemoglobinopatias/genética , Mutação , China , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Medição de Risco , Análise de Sequência de DNA
15.
Int J Lab Hematol ; 41(5): 650-656, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31271507

RESUMO

INTRODUCTION: Thalassemias and hemoglobinopathies are the most prevalent inherited anemias detected in South East Asians. These disorders represent not only a clinical health problem but also a socioeconomic problem for this region. Regarding the prevention and control of thalassemias and hemoglobinopathies in the Lao PDR, screening and diagnostic strategies should be strongly considered. The knowledge about the prevalence and molecular genotyping of thalassemias and hemoglobinopathies among the Lao Loum group, which includes the majority of Lao people, is now limited, making the prevention and control of thalassemias difficult. METHODS: This study aimed to determine the prevalence of thalassemia among Lao Loum subjects of reproductive age. Multiplex gap PCR and direct sequencing were used to investigate the mutations of α-globin and ß-globin genes. RESULTS: Thalassemias and hemoglobinopathies were detected in 154 of 354 (43.50%) patients, and 22 different genotypes were identified in this cohort. Remarkably, high frequencies of hemoglobin E, α0 -thalassemia (--SEA ), and α+ -thalassemia (-α3.7 ) were noted. A variety of hematologic features was observed, including co-inheritance of heterozygous HbE and heterozygous α-thalassemia, which was associated with significantly lower levels of MCV and MCH values than those observed in typical HbE heterozygotes. Female participants who were heterozygous for ß0 or co-inheritance of heterozygous ßE with heterozygous α-thalassemia exhibited mild anemia. CONCLUSION: Our data show that thalassemias and hemoglobinopathies have become health problems imposing a serious burden in the Lao PDR. Prevention programs aimed at decreasing the incidence of severe thalassemia diseases should be designed and initiated.


Assuntos
Hemoglobina E/genética , Hemoglobinopatias/genética , Mutação , alfa-Globinas/genética , Talassemia alfa/genética , Talassemia beta/genética , Adolescente , Feminino , Frequência do Gene , Testes Genéticos/métodos , Genótipo , Hemoglobinopatias/diagnóstico , Hemoglobinopatias/epidemiologia , Humanos , Laos/epidemiologia , Masculino , Prevalência , Adulto Jovem , Talassemia alfa/diagnóstico , Talassemia alfa/epidemiologia , Talassemia beta/diagnóstico , Talassemia beta/epidemiologia
16.
Hemoglobin ; 43(2): 145-147, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31268351

RESUMO

More than 900 abnormal hemoglobin (Hb) ß chain variants have now been characterized. The majority are due to point mutations resulting in a single amino acid substitution within the globin gene involved, with nearly twice as many ß chain variants identified compared to α chain variants. Although most of these variants are clinically and hematologically silent, they can interact with different thalassemia mutations, which could sometimes render laboratory diagnostics in a routine setting difficult. In this study, we present a case of coinheritance of Hb City of Hope [ß69(E13)Gly→Ser; HBB: c.208G>A] and ß-thalassemia (ß-thal), that compromises the molecular diagnosis of ß-thal trait.


Assuntos
Códon/genética , Hemoglobinas Anormais/genética , Mutagênese Insercional , Patologia Molecular/métodos , Globinas beta/genética , Talassemia beta/diagnóstico , Hemoglobinopatias/genética , Heterozigoto , Humanos
17.
Hum Mol Genet ; 28(R1): R24-R30, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31322165

RESUMO

Recently, gene therapy clinical trials have been successfully applied to hemoglobinopathies, such as sickle cell disease (SCD) and ß-thalassemia. Among the great discoveries that led to the design of genetic approaches to cure these disorders is the discovery of the ß-globin locus control region and several associated transcription factors, which determine hemoglobin switching as well as high-level, erythroid-specific expression of genes at the ß-globin locus. Moreover, increasing evidence shows that lentiviral vectors are efficient tools to insert large DNA elements into nondividing hematopoietic stem cells, showing reassuring safe integration profiles. Alternatively, genome editing could restore expression of fetal hemoglobin or target specific mutations to restore expression of the wild-type ß-globin gene. The most recent clinical trials for ß-thalassemia and SCD are showing promising outcomes: patients were able to discontinue transfusions or had reduced transfusion requirements. However, toxic myeloablation and the high cost of current ex vivo hematopoietic stem cell gene therapy platforms represent a barrier to a widespread application of these approaches. In this review, we summarize these gene therapy strategies and ongoing clinical trials. Finally, we discuss possible strategies to improve outcomes, reduce myeloablative regimens and future challenges to reduce the cost of gene therapy platform.


Assuntos
Terapia Genética , Hemoglobinopatias/genética , Hemoglobinopatias/terapia , Animais , Ensaios Clínicos como Assunto , Regulação da Expressão Gênica , Predisposição Genética para Doença , Terapia Genética/efeitos adversos , Terapia Genética/economia , Terapia Genética/métodos , Terapia Genética/tendências , Vetores Genéticos/genética , Transplante de Células-Tronco Hematopoéticas , Hemoglobinas/genética , Humanos , Mutação , Transdução Genética , Resultado do Tratamento
18.
Hemoglobin ; 43(2): 132-136, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31190580

RESUMO

We report four cases of compound heterozygotes for Hb S (HBB: c.20A>T) and a rare ß0-thalassemia (ß0-thal) mutation, Hb Westdale (HBB: c.380_396delTGCAGGCTGCCTATCAG), characterized by a 17 bp deletion between codons 126 to 131 in exon 3 of the ß-globin gene of human hemoglobin (Hb) confirmed by direct ß-globin gene sequencing. All four cases were from four unrelated families belonging to the Agharia caste, an endogamous ethnic community of the Sundargarh and Jharsuguda districts of Odisha State, India. Detailed observations indicated that all four cases of Hb S/Hb Westdale were clinically severe. On family screening, six family members were found to be heterozygous for Hb Westdale and were asymptomatic. Deletional α-thalassemia (α-thal) and XmnI polymorphism were studied for all the Hb Westdale cases. The Hb S/Hb Westdale cases had an early median age at onset of symptoms and presentation, more requirement of blood transfusions, splenomegaly and hepatomegaly and were found to be clinically more severe when compared with the Hb S-ß-thal with IVS-I-5 (G>C) (HBB: c.92 + 5G>C) cases. Overall, the findings indicate that this rare and hitherto unreported compound heterozygosity of Hb S/Hb Westdale is a clinically significant hemoglobinopathy and its finding in a large endogamous community of Odisha State, India will have important implication in the epidemiology and understanding of the clinical spectrum of sickle cell disease in Indian context and prenatal diagnosis.


Assuntos
Hemoglobina Falciforme/genética , Hemoglobinopatias/etnologia , Hemoglobinas Anormais/genética , Heterozigoto , Mutação , Globinas beta/genética , Transfusão de Sangue , Hemoglobinopatias/genética , Hemoglobinopatias/patologia , Hemoglobinopatias/terapia , Hepatomegalia/etiologia , Humanos , Índia/etnologia , Polimorfismo de Nucleotídeo Único , Deleção de Sequência , Esplenomegalia/etiologia
20.
Clin Chem ; 65(8): 986-994, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31040099

RESUMO

BACKGROUND: Hemoglobinopathies and thalassemias are the most common genetically determined disorders. Current screening methods include cation-exchange HPLC and electrophoresis, the results of which can be ambiguous because of limited resolving power. Subsequently, laborious genetic testing is required for confirmation. METHODS: We performed a top-down tandem mass spectrometry (MS/MS) approach with a fast data acquisition (3 min), ultrahigh mass accuracy, and extensive residue cleavage by use of positive electrospray ionization 21 Tesla Fourier transform ion cyclotron resonance-tandem mass spectrometry (21 T FT-ICR MS/MS) for hemoglobin (Hb) variant de novo sequencing and ß-thalassemia diagnosis. RESULTS: We correctly identified all Hb variants in blind analysis of 18 samples, including the first characterization of homozygous Hb Himeji variant. In addition, an Hb heterozygous variant with isotopologue mass spacing as small as 0.0194 Da (Hb AD) was resolved in both precursor ion mass spectrum (MS1) and product ion mass spectrum (MS2). In blind analysis, we also observed that the abundance ratio between intact δ and ß subunits (δ/ß) or the abundance ratio between intact δ and α subunits (δ/α) could serve to diagnose ß-thalassemia trait caused by a mutation in 1 HBB gene. CONCLUSIONS: We found that 21 T FT-ICR MS/MS provides a benchmark for top-down MS/MS analysis of blood Hb. The present method has the potential to be translated to lower resolving power mass spectrometers (lower field FT-ICR mass spectrometry and Orbitrap) for Hb variant analysis (by MS1 and MS2) and ß-thalassemia diagnosis (MS1).


Assuntos
Análise de Fourier , Hemoglobinopatias/sangue , Hemoglobinas/química , Espectrometria de Massas/métodos , Espectrometria de Massas em Tandem/métodos , Talassemia beta/sangue , Sequência de Aminoácidos , Ciclotrons , Variação Genética , Hemoglobinopatias/genética , Humanos , Sensibilidade e Especificidade , Análise de Sequência de Proteína/métodos , alfa-Globinas/química , Globinas beta/química , Talassemia beta/genética , Globinas delta/química
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