RESUMEN

Despite several existing laboratory-based studies of hemoglobin (Hb) E (HBB:c.79 G > A)/ ß (nucleotide (NT) -28 A > G) (HBB:c.-78 A > G) -thalassemia, no reports have ever provided clinical severity information as well as dependency of blood transfusion. Previously, a comparative study of community- and hospital-recruited Hb E/ß-thalassemia subjects was conducted in the lower northern Thailand between June 2020 and December 2021. A mobile medical team visited each community hospital on-site, collecting clinical severity parameters, and conducting Hb and DNA analyses. The control included Hb E/ß-thalassemia patients undergoing transfusions. Subgroup study of adult Hb E/ß (NT -28 A > G) -thalassemia subjects was subsequently conducted. Additional pediatric individuals were recruited from prenatal diagnosis databases. Twenty adult and nine pediatric subjects were enrolled; all were classified as having mild disease severity. Twenty-two individuals (75.9 %) were asymptomatic. Six adults (20.7 %) required blood transfusion. The mean Hb level of subjects without transfusion (23 [79.3 %]) was 10.77 ± 1.10 g/dL. Hb analysis revealed a distinct EFA pattern with low Hb F fraction. The positive impact of genetic modifiers could not be statistically demonstrated except rs7482144-XmnI. These findings could provide essential information for parents carrying fetuses with Hb E/ß (NT -28 A > G) -thalassemia.

Asunto(s)

Hemoglobina E , Talasemia beta , Humanos , Hemoglobina E/genética , Femenino , Masculino , Adulto , Talasemia beta/genética , Talasemia beta/sangre , Talasemia beta/diagnóstico , Globinas beta/genética , Tailandia , Niño , Persona de Mediana Edad , Adolescente , Estudios de Cohortes , Preescolar , Adulto Joven , Transfusión Sanguínea , Hospitales

RESUMEN

To investigate the impact of different 5' untranslated regions (UTRs) on mRNA vaccine translation efficiency, five dual-reporter gene expression plasmids with different 5'UTRs were constructed. The corresponding mRNA transcripts were transcribed and capped in vitro. By comparing the expression levels of reporter genes with different 5'UTRs, we identified the 5'UTR associated with the highest expression level. Subsequently, HIVgp145 mRNA vaccines containing various 5'UTRs were constructed and verified. The results demonstrated that mRNA 3 (ß-globin 5'UTR) displayed the greatest number of green fluorescence-positive cells and the highest luciferase fluorescence intensity in the reporter gene expression system. Further, among the HIVgp145 mRNA vaccines with different 5'UTRs, mRNA 7 (ß-globin 5'UTR) exhibited the highest level of expression. These findings indicate that it is feasible to use the 5'UTR of ß-globin in an mRNA vaccine, laying the foundation for animal immunogenicity testing.

Asunto(s)

Regiones no Traducidas 5' , Genes Reporteros , Vacunas de ARNm , Humanos , ARN Mensajero/genética , Globinas beta/genética , Animales , Células HEK293

RESUMEN

RNA polymerase II (Pol II) dysfunction is frequently implied in human disease. Understanding its functional mechanism is essential for designing innovative therapeutic strategies. To visualize its supra-molecular interactions with genes and nascent RNA, we generated a human cell line carrying ~335 consecutive copies of a recombinant ß-globin gene. Confocal microscopy showed that Pol II was not homogeneously concentrated around these identical gene copies. Moreover, Pol II signals partially overlapped with the genes and their nascent RNA, revealing extensive compartmentalization. Using a cell line carrying a single copy of the ß-globin gene, we also tested if the binding of catalytically dead CRISPR-associated system 9 (dCas9) to different gene regions affected Pol II transcriptional activity. We assessed Pol II localization and nascent RNA levels using chromatin immunoprecipitation and droplet digital reverse transcription PCR, respectively. Some enrichment of transcriptionally paused Pol II accumulated in the promoter region was detected in a strand-specific way of gRNA binding, and there was no decrease in nascent RNA levels. Pol II preserved its transcriptional activity in the presence of DNA-bound dCas9. Our findings contribute further insight into the complex mechanism of mRNA transcription in human cells.

Asunto(s)

ARN Polimerasa II , Transcripción Genética , Globinas beta , Humanos , ARN Polimerasa II/metabolismo , ARN Polimerasa II/genética , Globinas beta/genética , Globinas beta/metabolismo , ADN/metabolismo , ADN/genética , Regiones Promotoras Genéticas , Proteína 9 Asociada a CRISPR/metabolismo , Proteína 9 Asociada a CRISPR/genética , Sistemas CRISPR-Cas , ARN/genética , ARN/metabolismo , ARN Guía de Sistemas CRISPR-Cas/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo , Línea Celular

RESUMEN

Hemoglobin Shaare Zedek (Hb SZ) is a rare structural α-Hb variant. Characterizing its genotype-phenotype relationship and genetic origin enhances diagnostic and clinical management insights. We studied a proband and six family members using high-performance liquid chromatography (HPLC), capillary electrophoresis (CE), PCR, and sequencing to analyze α- and ß-globin genes and α-globin haplotypes. Pathogenicity predictions and a rapid diagnostic method were developed. The proband, his father, grandfather, and aunt had Hb migrating to the HbH-zone on CE and elevated fetal hemoglobin (HbF) on HPLC. Direct sequencing identified an A to G mutation at codon 56 of the α2-globin gene, characteristic of Hb SZ. Additionally, the proband carried a ß-globin gene mutation [HBB.52A>T]. Mild thalassemia-like changes were observed in the proband, whereas individuals with only the Hb SZ variant did not exhibit these changes. Pathogenicity predictions indicated that Hb SZ is benign. The variant can be identified using restriction fragment length polymorphism (RFLP) and allele-specific PCR. The Thai variant of Hb SZ is associated with the haplotype [- - M - - - -]. Hb SZ is a non-pathological variant that minimally affects red blood cell parameters, even when it coexists with ß0-thalassemia. HPLC and CE systems cannot distinguish it from other Hbs, necessitating DNA analysis for accurate diagnosis.

Asunto(s)

Hemoglobinas Anormales , Globinas beta , Talasemia beta , Adulto , Femenino , Humanos , Masculino , Globinas alfa/genética , Globinas beta/genética , Talasemia beta/genética , Talasemia beta/diagnóstico , Haplotipos , Hemoglobinas Anormales/genética , Mutación , Electroforesis Capilar , Cromatografía Líquida de Alta Presión

RESUMEN

Genetic mutations in the ß-globin gene lead to a decrease or removal of the ß-globin chain, causing the build-up of unstable alpha-hemoglobin. This condition is referred to as beta-thalassemia (BT). The present treatment strategies primarily target the correction of defective erythropoiesis, with a particular emphasis on gene therapy and hematopoietic stem cell transplantation. However, the presence of inefficient erythropoiesis in BT bone marrow (BM) is likely to disturb the previously functioning BM microenvironment. This includes accumulation of various macromolecules, damage to hematopoietic function, destruction of bone cell production and damage to osteoblast(OBs), and so on. In addition, the changes of BT BM microenvironment may have a certain correlation with the occurrence of hematological malignancies. Correction of the microenvironment can be achieved through treatments such as iron chelation, antioxidants, hypoglycemia, and biologics. Hence, This review describes damage in the BT BM microenvironment and some potential remedies.

Asunto(s)

Médula Ósea , Microambiente Celular , Talasemia beta , Humanos , Médula Ósea/patología , Médula Ósea/metabolismo , Talasemia beta/terapia , Terapia Genética , Animales , Talasemia/terapia , Eritropoyesis , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Quelantes del Hierro/uso terapéutico , Globinas beta/genética

RESUMEN

Sheep were domesticated in the Fertile Crescent and then spread globally, where they have been encountering various environmental conditions. The Tibetan sheep has adapted to high altitudes on the Qinghai-Tibet Plateau over the past 3000 years. To explore genomic variants associated with high-altitude adaptation in Tibetan sheep, we analyzed Illumina short-reads of 994 whole genomes representing ∼ 60 sheep breeds/populations at varied altitudes, PacBio High fidelity (HiFi) reads of 13 breeds, and 96 transcriptomes from 12 sheep organs. Association testing between the inhabited altitudes and 34,298,967 variants was conducted to investigate the genetic architecture of altitude adaptation. Highly accurate HiFi reads were used to complement the current ovine reference assembly at the most significantly associated ß-globin locus and to validate the presence of two haplotypes A and B among 13 sheep breeds. The haplotype A carried two homologous gene clusters: (1) HBE1, HBE2, HBB-like, and HBBC, and (2) HBE1-like, HBE2-like, HBB-like, and HBB; while the haplotype B lacked the first cluster. The high-altitude sheep showed highly frequent or nearly fixed haplotype A, while the low-altitude sheep dominated by haplotype B. We further demonstrated that sheep with haplotype A had an increased hemoglobin-O2 affinity compared with those carrying haplotype B. Another highly associated genomic region contained the EGLN1 gene which showed varied expression between high-altitude and low-altitude sheep. Our results provide evidence that the rapid adaptive evolution of advantageous alleles play an important role in facilitating the environmental adaptation of Tibetan sheep.

Asunto(s)

Altitud , Haplotipos , Animales , Ovinos/genética , Haplotipos/genética , Adaptación Fisiológica/genética , Transcriptoma/genética , Polimorfismo de Nucleótido Simple/genética , Proteómica/métodos , Globinas beta/genética , Aclimatación/genética , Tibet , Multiómica

RESUMEN

Sickle cell disease is a growing health burden afflicting millions around the world. Clinical observation and laboratory studies have shown that the severity of sickle cell disease is ameliorated in individuals who have elevated levels of fetal hemoglobin. Additional pharmacologic agents to induce sufficient fetal hemoglobin to diminish clinical severity is an unmet medical need. We recently found that up-regulation of peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α) can induce fetal hemoglobin synthesis in human primary erythroblasts. Here, we report that a small molecule, SR-18292, increases PGC-1α leading to enhanced fetal hemoglobin expression in human erythroid cells, ß-globin yeast artificial chromosome mice, and sickle cell disease mice. In SR-18292-treated sickle mice, sickled red blood cells are significantly reduced, and disease complications are alleviated. SR-18292, or agents in its class, could be a promising additional therapeutic for sickle cell disease.

Asunto(s)

Anemia de Células Falciformes , Antidrepanocíticos , Hemoglobina Fetal , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma , Anemia de Células Falciformes/tratamiento farmacológico , Anemia de Células Falciformes/metabolismo , Anemia de Células Falciformes/patología , Hemoglobina Fetal/metabolismo , Hemoglobina Fetal/genética , Animales , Humanos , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/metabolismo , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/genética , Ratones , Antidrepanocíticos/farmacología , Antidrepanocíticos/uso terapéutico , Modelos Animales de Enfermedad , Globinas beta/genética , Globinas beta/metabolismo

RESUMEN

Isothermal nucleic acid amplification tests have the potential to improve disease diagnosis at the point of care, but it remains challenging to develop multiplexed tests that can detect ≥3 targets or to detect point mutations that may cause disease. These capabilities are critical to enabling informed clinical decision-making for many applications, such as sickle cell disease (SCD). To address this, we describe the development of a multiplexed allele-specific recombinase polymerase amplification (RPA) assay with lateral flow readout. We first characterize the specificity of RPA using primer design strategies employed in PCR to achieve point mutation detection, and demonstrate the utility of these strategies in achieving selective isothermal amplification and detection of genomic DNA encoding for the healthy ßA globin allele, or genomic DNA containing point mutations encoding for pathologic ßS and ßC globin alleles, which are responsible for most sickle cell disorders. We then optimize reaction conditions to achieve multiplexed amplification and identification of the three alleles in a single reaction. Finally, we perform a small pilot study with 20 extracted genomic DNA samples from SCD patients and healthy volunteers - of the 13 samples with valid results, the assay demonstrated 100% sensitivity and 100% specificity for detecting pathologic alleles, and an overall accuracy of 92.3% for genotype prediction. This multiplexed assay is rapid, minimally instrumented, and when combined with point-of-care sample preparation, could enable DNA-based diagnosis of SCD in low-resource settings. The strategies reported here could be applied to other challenges, such as detection of mutations that confer drug resistance.

Asunto(s)

Alelos , Anemia de Células Falciformes , Técnicas de Amplificación de Ácido Nucleico , Recombinasas , Anemia de Células Falciformes/genética , Anemia de Células Falciformes/diagnóstico , Humanos , Recombinasas/metabolismo , Globinas beta/genética , Mutación Puntual

RESUMEN

AIM: To develop a non-invasive prenatal test for beta-hemoglobinopathies based on analyzing maternal plasma by using next generation sequencing. METHODS: We applied next generation sequencing (NGS) of maternal plasma to the non-invasive prenatal testing (NIPT) of autosomal recessive diseases, sickle cell disease and beta-thalassemia. Using the Illumina MiSeq, we sequenced plasma libraries obtained via a Twist Bioscience probe capture panel covering 4 Kb of chromosome 11, including the beta-globin (HBB) gene and >450 genomic single-nucleotide polymorphisms (SNPs) used to estimate the fetal fraction (FF). The FF is estimated by counting paternally transmitted allelic sequence reads present in the plasma but absent in the mother. We inferred fetal beta-globin genotypes by comparing the observed mutation (Mut) and reference (Ref) read ratios to those expected for the three possible fetal genotypes (Mut/Mut; Mut/Ref; Ref/Ref), based on the FF. RESULTS: We bioinformatically enriched the FF by excluding reads over a specified length via in-silico size selection (ISS), favoring the shorter fetal reads, which increased fetal genotype prediction accuracy. Finally, we determined the parental HBB haplotypes, which allowed us to use the read ratios observed at linked SNPs to help predict the fetal genotype at the mutation site(s). We determined HBB haplotypes via Oxford Nanopore MinION sequencing of a 2.2 kb amplicon and aligned these sequences using Soft Genetics' NextGENe LR software. CONCLUSION: The combined use of ISS and HBB haplotypes enabled us to correctly predict fetal genotypes in cases where the prediction based on variant read ratios alone was incorrect.

Asunto(s)

Haplotipos , Secuenciación de Nucleótidos de Alto Rendimiento , Polimorfismo de Nucleótido Simple , Humanos , Femenino , Embarazo , Diagnóstico Prenatal/métodos , Talasemia beta/genética , Talasemia beta/diagnóstico , Pruebas Prenatales no Invasivas , Globinas beta/genética , Genotipo , Hemoglobinopatías/genética , Hemoglobinopatías/diagnóstico , Anemia de Células Falciformes/genética , Anemia de Células Falciformes/diagnóstico

RESUMEN

Sickle cell disease is a devastating blood disorder that originates from a single point mutation in the HBB gene coding for hemoglobin. Here, we develop a GMP-compatible TALEN-mediated gene editing process enabling efficient HBB correction via a DNA repair template while minimizing risks associated with HBB inactivation. Comparing viral versus non-viral DNA repair template delivery in hematopoietic stem and progenitor cells in vitro, both strategies achieve comparable HBB correction and result in over 50% expression of normal adult hemoglobin in red blood cells without inducing ß-thalassemic phenotype. In an immunodeficient female mouse model, transplanted cells edited with the non-viral strategy exhibit higher engraftment and gene correction levels compared to those edited with the viral strategy. Transcriptomic analysis reveals that non-viral DNA repair template delivery mitigates P53-mediated toxicity and preserves high levels of long-term hematopoietic stem cells. This work paves the way for TALEN-based autologous gene therapy for sickle cell disease.

Asunto(s)

Anemia de Células Falciformes , Edición Génica , Terapia Genética , Células Madre Hematopoyéticas , Nucleasas de los Efectores Tipo Activadores de la Transcripción , Anemia de Células Falciformes/terapia , Anemia de Células Falciformes/genética , Edición Génica/métodos , Animales , Células Madre Hematopoyéticas/metabolismo , Humanos , Femenino , Ratones , Terapia Genética/métodos , Nucleasas de los Efectores Tipo Activadores de la Transcripción/metabolismo , Nucleasas de los Efectores Tipo Activadores de la Transcripción/genética , Trasplante de Células Madre Hematopoyéticas , Globinas beta/genética , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Reparación del ADN , Mutación , Talasemia beta/terapia , Talasemia beta/genética , Modelos Animales de Enfermedad , Técnicas de Transferencia de Gen

RESUMEN

Lambs harboring the Hb-AA ß-globin haplotype present improved cell-mediated responses and increased resistance against Haemonchus contortus infection. The aim of the present study was to compare the effect of sex and ß-globin haplotypes on specific humoral responses and phenotypes of resistance during H. contortus infection in Morada Nova sheep. As expected, females displayed stronger resistance during the first and second experimental challenges. Differential systemic humoral immune responses were observed comparing sex groups, in which higher levels of specific antibodies targeting 24 kDa excretory-secretory (ES24) protein of H. contortus of IgG and IgM antibodies were respectively observed as predominant isotypes in males and females. The IgM levels were significantly correlated with phenotypes of resistance, evaluated by packed cell volume and fecal egg counts. To our knowledge this is the first study reporting divergent humoral responses profiles to H. contortus infection between male and female sheep. The impact of ß-globin haplotypes was less pronounced in females compared to males. Notably, only males showed significant weight differences across haplotypes, with Hb-AA lambs being the heaviest. Additionally, Hb-AA males had significantly higher PCV (indicating better red blood cell health) and lower FEC (indicating lower parasite burden). These findings suggest a more pronounced effect of ß-globin polymorphisms on H. contortus infection in males, potentially due to their generally weaker resistance compared to females. This study highlights the importance of sex and ß-globin haplotypes in shaping immune responses to H. contortus infection. Specifically, IgM antibodies targeting the ES24 protein appear to play a crucial role in host-parasite interactions and may hold promise for therapeutic development.

Asunto(s)

Hemoncosis , Haemonchus , Inmunidad Humoral , Polimorfismo Genético , Enfermedades de las Ovejas , Globinas beta , Animales , Femenino , Masculino , Anticuerpos Antihelmínticos/inmunología , Antígenos Helmínticos/inmunología , Globinas beta/genética , Globinas beta/inmunología , Resistencia a la Enfermedad/inmunología , Resistencia a la Enfermedad/genética , Hemoncosis/veterinaria , Hemoncosis/inmunología , Hemoncosis/parasitología , Haemonchus/inmunología , Haplotipos , Proteínas del Helminto/inmunología , Proteínas del Helminto/genética , Proteínas del Helminto/metabolismo , Inmunoglobulina G/inmunología , Inmunoglobulina G/metabolismo , Inmunoglobulina M/inmunología , Inmunoglobulina M/metabolismo , Factores Sexuales , Ovinos/inmunología , Enfermedades de las Ovejas/inmunología , Enfermedades de las Ovejas/parasitología , Enfermedades de las Ovejas/genética

RESUMEN

Intronic deletions that critically shorten donor-to-branchpoint (D-BP) distance of a precursor mRNA impose biophysical space constraint on assembly of the U1/U2 spliceosomal complex, leading to canonical splicing failure. Here we use a series of ß-globin (HBB) gene constructs with intron 1 deletions to define D-BP lengths that present low/no risk of mis-splicing and lengths which are critically short and likely elicit clinically relevant mis-splicing. We extend our previous observation in EMD intron 5 of 46 nt as the minimal productive D-BP length, demonstrating spliceosome assembly constraint persists at D-BP lengths of 47-56 nt. We exploit the common HBB exon 1 ß-thalassemia variant that strengthens a cryptic donor (NM_000518.5(HBB):c.79G > A) to provide a simple barometer for the earliest signs of space constraint, via cryptic donor activation. For clinical evaluation of intronic deletions, we assert D-BP lengths > 60 nt present low mis-splicing risk while space constraint increases exponentially with D-BP lengths < 55 nt, with critical risk and profound splicing abnormalities with D-BP lengths < 50 nt.

Asunto(s)

Intrones , Globinas beta , Humanos , Globinas beta/genética , Empalme del ARN , Talasemia beta/genética , Talasemia beta/diagnóstico , Sitios de Empalme de ARN , Eliminación de Secuencia , Empalmosomas/genética , Empalmosomas/metabolismo

RESUMEN

ß0/ß0 thalassemia is the most severe type of transfusion-dependent ß-thalassemia (TDT) and is still a challenge facing lentiviral gene therapy. Here, we report the interim analysis of a single-center, single-arm pilot trial (NCT05015920) evaluating the safety and efficacy of a ß-globin expression-optimized and insulator-engineered lentivirus-modified cell product (BD211) in ß0/ß0 TDT. Two female children were enrolled, infused with BD211, and followed up for an average of 25.5 months. Engraftment of genetically modified hematopoietic stem and progenitor cells was successful and sustained in both patients. No unexpected safety issues occurred during conditioning or after infusion. Both patients achieved transfusion independence for over 22 months. The treatment extended the lifespan of red blood cells by over 42 days. Single-cell DNA/RNA-sequencing analysis of the dynamic changes of gene-modified cells, transgene expression, and oncogene activation showed no notable adverse effects. Optimized lentiviral gene therapy may safely and effectively treat all ß-thalassemia.

Asunto(s)

Terapia Genética , Lentivirus , Globinas beta , Talasemia beta , Humanos , Talasemia beta/terapia , Talasemia beta/genética , Proyectos Piloto , Femenino , Lentivirus/genética , Globinas beta/genética , Niño , Transfusión Sanguínea , Preescolar

RESUMEN

ABSTRACT: It has been known for over half a century that throughout ontogeny, humans produce different forms of hemoglobin, a tetramer of α- and ß-like hemoglobin chains. The switch from fetal to adult hemoglobin occurs around the time of birth when erythropoiesis shifts from the fetal liver to the bone marrow. Naturally, diseases caused by defective adult ß-globin genes, such as sickle cell disease and ß-thalassemia, manifest themselves as the production of fetal hemoglobin fades. Reversal of this developmental switch has been a major goal to treat these diseases and has been a driving force to understand its underlying molecular biology. Several review articles have illustrated the long and at times arduous paths that led to the discovery of the first transcriptional regulators involved in this process. Here, we survey recent developments spurred by the discovery of CRISPR tools that enabled for the first time high-throughput genetic screens for new molecules that impact the fetal-to-adult hemoglobin switch. Numerous opportunities for therapeutic intervention have thus come to light, offering hope for effective pharmacologic intervention for patients for whom gene therapy is out of reach.

Asunto(s)

Hemoglobina Fetal , Humanos , Hemoglobina Fetal/genética , Hemoglobina Fetal/metabolismo , Animales , Anemia de Células Falciformes/genética , Anemia de Células Falciformes/terapia , Anemia de Células Falciformes/metabolismo , Talasemia beta/genética , Talasemia beta/terapia , Talasemia beta/metabolismo , Eritropoyesis/genética , Globinas beta/genética , Globinas beta/metabolismo

RESUMEN

Hemoglobin (Hb) Lepore is a rare deletional δß-thalassemia caused by the fusion between delta-beta genes, and cannot be identified by traditional thaltassemia gene testing technology. The aim of this study was to conduct molecular diagnosis and clinical analysis of Hb Lepore in four unrelated Chinese families using third generation sequencing. Decreased levels of mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH) and an abnormal Hb band were observed in the probands of the four families. However, no common α and ß-thalassemia variants were detected in the enrolled families using polymerase chain reaction-reverse dot blot hybridization based traditional thalassemia gene testing. Further third-generation sequencing revealed similar Hb Lepore-Boston-Washington variants in all the patients, which were resulted from partial coverage of the HBB and HBD globin genes, leading to the formation of a delta-beta fusion gene. Specific gap-PCR and Sanger sequencing confirmed that all the patients carried a similar Hb Lepore-Boston-Washington heterozygote. In addition, decreased levels of MCH and Hb A2 were observed in the proband's wife of family 2, an extremely rare variant of Hb Nanchang (GGT > AGT) (HBA2:c.46G > A) was identified by third-generation sequencing and further confirmed by Sanger sequencing. This present study was the first to report the similar Hb Lepore-Boston-Washington in Chinese population. By combining the utilization of Hb capillary electrophoresis and third-generation sequencing, the screening and diagnosis of Hb Lepore can be effectively enhanced.

Asunto(s)

Pueblo Asiatico , Hemoglobinas Anormales , Adulto , Femenino , Humanos , Masculino , Pueblo Asiatico/genética , Globinas beta/genética , Talasemia beta/genética , Talasemia beta/diagnóstico , Talasemia beta/sangre , China , Pueblos del Este de Asia , Hemoglobinas Anormales/genética , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Linaje

RESUMEN

Newborn screening identified a Chinese-Canadian infant who was positive for possible ß-thalassemia (ß-thal). Detailed family studies demonstrated that the proband was a compound heterozygote for the Chinese Gγ(Aγδß)0-thal deletion and a novel frameshift mutation within exon 3 (HBB:c.336dup), and heterozygous for the Southeast Asian α-thal deletion (--SEA/αα). This case illustrates the importance of follow-up molecular testing of positive newborn screening results to confirm the diagnosis and define risks for future pregnancies.

Asunto(s)

Genotipo , Tamizaje Neonatal , Globinas beta , Talasemia beta , Femenino , Humanos , Recién Nacido , Masculino , Globinas beta/genética , Talasemia beta/genética , Talasemia beta/diagnóstico , Mutación del Sistema de Lectura , Heterocigoto , Mutación , Linaje

Asunto(s)

Haplotipos , Globinas beta , Globinas beta/genética , Animales , Haplotipos/genética , Ovinos/genética , Adaptación Fisiológica/genética

RESUMEN

ß-Thalassemia is a single-gene disease caused by mutations in ß-globin and has a distinct geographical characteristics. Current treatment for patients with moderate to severe thalassemia has mainly relied on long-term blood transfusion and/or hematopoietic stem cell transplantation. B cell lymphoma/leukemia 11A (BCL11A) as a transcriptional repressor plays a vital role in monitoring γ/ß hemoglobin switching, maintaining the normal function of hematopoietic stem cells, and regulating erythrocyte differentiation and lymphocyte development. With the rapid progress in gene editing technology, the BCL11A as a therapeutic target for ß-thalassemia has shown promising results. This article has systematically summarized the regulatory mechanism and therapeutic potential of the BCL11A, with an aim to provide new ideas for the treatment of ß-thalassemia.

Asunto(s)

Proteínas Represoras , Talasemia beta , Humanos , Proteínas Represoras/genética , Talasemia beta/genética , Talasemia beta/terapia , Hemoglobina Fetal/genética , Factores de Transcripción , Globinas beta/genética

RESUMEN

OBJECTIVE: To analyze the mutations of globin genes among patients suspected for thalassemia from the Shanghai area. METHODS: A total of 4 644 patients diagnosed at Ruijin Hospital, Shanghai Jiao Tong University School of Medicine between June 2016 and December 2019 were selected as the study subjects. The patients were tested for common mutations associated with thalassemia gene by Gap-PCR and reverse dot blotting (RDB). Patients were suspected to harbor rare mutations based on the inconsistency between hematological phenotypes and results of common mutation detection, and were further analyzed by Gap-PCR and Sanger sequencing. RESULTS: Among the 4 644 patients, 2 194 (47.24%) were found to carry common thalassemia mutations, among which 701 (15.09%) were α-thalassemia, 1 448 (31.18%) were ß-thalassemia, and 45 (0.97%) were both α- and ß-thalassemia. Forty six samples were found to harbor rare mutations, which included 17 α-globin gene and 29 ß-globin gene mutations. CD77(CCC>ACC) (HBA2: c.232C>A) of the α-globin gene, NG_000007.3: g.70567_71015del449, codon 102(-A) (HBB: c.308_308delA) and IVS-Ⅱ-636 (A>G) (HBB: c.316-215A>G) of the ß-globin gene were previously unreported new types of globin gene mutations. CONCLUSION: Among the 4 644 patients, the detection rate for common thalassemia mutations was 47.24%, whilst 46 samples were detected with rare gene mutations. The type of gene mutation types were diverse in the Shanghai area. The study has provided more accurate results for genetic diagnosis and counseling.

Asunto(s)

Talasemia alfa , Talasemia beta , Humanos , Talasemia beta/genética , Talasemia beta/diagnóstico , Genotipo , Globinas beta/genética , China , Mutación , Talasemia alfa/genética , Globinas alfa/genética

RESUMEN

We report two hemoglobinopathy cases involving a novel ß-thalassemia (ß-thal) nonsense mutation, HBB:c.199A > T. One patient had Hb S/ß-thal, and a second unrelated patient had Hb D-Punjab/ß-thal. The HBB:c.199A > T mutation introduces a premature termination codon at amino acid codon 66 (AAA→TAA) in exon 2, resulting in typical high Hb A2 ß0-thal.

Asunto(s)

Hemoglobinopatías , Talasemia beta , Humanos , Globinas beta/genética , Talasemia beta/diagnóstico , Talasemia beta/genética , Codón sin Sentido , Hemoglobinopatías/genética , Mutación